Hai District Council - Class Seven Monthly Examination (With Marking Scheme)

HAI DISTRICT COUNCIL

JANUARY MONTHLY EXAMINATION - CLASS SEVEN

2024 Examination Series

Examination Overview

The Class Seven January Monthly Examination represents a critical assessment in the Tanzanian primary education system, designed to comprehensively evaluate students' mastery of core subjects as they approach the conclusion of their primary education journey. This examination series tests both foundational knowledge and higher-order thinking skills across six essential subjects.

The Mathematics paper challenges students with complex arithmetic operations, fractions, decimals, percentages, geometry, and word problems, requiring both computational accuracy and logical reasoning. The Civic and Moral Education examination assesses understanding of Tanzanian governance structures, national symbols, citizen responsibilities, and ethical principles, preparing students for active citizenship.

Kiswahili language testing covers advanced grammar, comprehension, poetry analysis, and formal writing skills, while English assessment focuses on grammar mastery, vocabulary, reading comprehension, and writing proficiency. Science and Technology papers test knowledge of scientific principles, environmental issues, and basic technological concepts, and Social Studies integrates geography, history, and current affairs to develop holistic understanding of society.

Each examination is carefully structured to align with the Tanzanian primary curriculum standards, with marking schemes provided to ensure consistent and fair evaluation across all schools in Hai District. These assessments serve as important preparation for the upcoming Primary School Leaving Examination (PSLE) and help identify areas where students may need additional support.

Examination Paper Samples

Mathematics

"348954 + 23579 = ______"

"Find the average harvest of maize sacks per year from the line graph"

Topics: Arithmetic, Fractions, Geometry, Graphs, Word Problems

Civic & Moral Education

"Who is responsible for protecting human rights and maintaining peace?"

"Explain two disadvantages of not being transparent"

Topics: Governance, National Symbols, Citizenship, Ethics

Kiswahili

"Chagua herufi ya jibu sahihi: Hali ya mazingira ni mbaya kwa sababu gani?"

"Panga sentensi zifuatazo kwa mtiririko sahihi"

Topics: Grammar, Comprehension, Poetry, Formal Writing

📚

KISWAHILI

Advanced Kiswahili examination covering grammar, comprehension, poetry analysis, and formal writing skills for Class Seven students.

📥 Download Exam 📝 Marking Scheme

🧮

MATHEMATICS

Comprehensive mathematics assessment covering arithmetic, fractions, geometry, graphs, and complex word problems.

📥 Download Exam 📝 Marking Scheme

🏛️

CIVIC AND MORAL

Civic education and moral studies covering Tanzanian governance, national symbols, citizenship, and ethical principles.

📥 Download Exam 📝 Marking Scheme

🔬

SCIENCE & TECHNOLOGY

Science and technology examination covering scientific principles, environmental issues, and basic technology concepts.

📥 Download Exam 📝 Marking Scheme

📖

ENGLISH

English language assessment focusing on advanced grammar, vocabulary, reading comprehension, and writing skills.

📥 Download Exam 📝 Marking Scheme

🌍

SOCIAL STUDIES

Integrated social studies examination covering geography, history, economics, and contemporary social issues.

📥 Download Exam 📝 Marking Scheme

Important Examination Information

• All examination papers are available in PDF format for easy download and printing.
• Marking schemes provide detailed answers and scoring guidelines for teachers.
• Examination duration: 2 hours 30 minutes for Mathematics, 2 hours for other subjects.
• Students must attempt all sections of each examination paper.
• Teachers should administer examinations under supervised conditions.
• Results should be submitted to the District Education Office by February 15, 2024.
• For technical support with downloads, contact the ICT Department at Hai District Council.

© 2024 Hai District Council. All examination materials are property of the Hai District Education Department.

Hai District Council - Class Four Monthly Examination (with marking schemes)

HAI DISTRICT COUNCIL

JANUARY MONTHLY EXAMINATION - CLASS FOUR

January 2024 Examination Series

Examination Overview

The January Monthly Examination for Class Four is a comprehensive assessment designed to evaluate students' understanding across six core subjects. This examination follows the Tanzanian primary education curriculum and aims to test both knowledge acquisition and practical application skills.

The examination papers cover fundamental concepts in Mathematics, English, Kiswahili, Science, Geography & Environment, and History & Moral Education. Each paper is structured to assess different cognitive levels from basic recall to analytical thinking. The Geography & Environment paper focuses on human-environment interactions, basic map reading, and environmental awareness. The Science examination tests understanding of health principles, nutrition, safety signs, and basic biological concepts. The English paper assesses language skills including grammar, vocabulary, and reading comprehension.

Marking schemes are provided for each subject to ensure standardized evaluation. These comprehensive examinations are crucial for tracking student progress, identifying learning gaps, and preparing students for future academic challenges. Teachers are encouraged to use the marking schemes consistently to maintain assessment integrity across the district.

Examination Papers (Sample Questions)

Geography & Environment

Sample: "My dream is to study about human being and his surroundings. What should I deal with?"

Topics: Physical features, water bodies, environmental conservation, economic activities.

Science

Sample: "What do we mean when we say complete meal?"

Topics: Health principles, nutrition, safety signs, environmental pollution.

English

Sample: "A brother of your father is your ______"

Topics: Grammar, vocabulary, reading comprehension, sentence structure.

📚

KISWAHILI

Examination paper and marking scheme for Kiswahili language covering grammar, comprehension, and writing skills.

Download Exam Paper Download Marking Scheme

🧮

MATHEMATICS

Mathematics examination covering arithmetic, basic geometry, and problem-solving skills for Class Four students.

Download Exam Paper Download Marking Scheme

🏛️

HISTORIA YA TANZANIA NA MAADILI

Tanzanian history and moral education examination covering historical events and ethical principles.

Download Exam Paper Download Marking Scheme

🌍

GEOGRAPHY AND ENVIRONMENT

Geography and environmental studies examination covering physical features, maps, and environmental conservation.

Download Exam Paper Download Marking Scheme

🔬

SCIENCE

Science examination covering health, nutrition, safety, and basic biological concepts for Class Four students.

Download Exam Paper Download Marking Scheme

📖

ENGLISH

English language examination covering grammar, vocabulary, reading comprehension, and writing skills.

Download Exam Paper Download Marking Scheme

Important Examination Notes:

1. All examination papers are in PDF format and can be downloaded from the Google Drive links provided.

2. Marking schemes are provided for teachers to ensure consistent and fair evaluation.

3. Examination duration for each subject is 2 hours unless otherwise specified.

4. Students should attempt all questions in the examination papers.

5. For any technical issues with downloads, please contact the Hai District Council Education Office.

HAI DISTRICT COUNCIL EDUCATION DEPARTMENT

P.O. Box 123, Hai, Kilimanjaro Region, Tanzania

Email: education@haidc.go.tz | Phone: +255 27 123 4567

© 2024 Hai District Council. All rights reserved.

FORM SIX PRE NATIONAL EXAMINATION PHYSICS 1 - SERIES 14 (With Comprehensive Solution)

UMOJA WA WAZAZI TANZANA

WARI SECONDARY SCHOOL

PRE-NATIONAL EXAMINATION SERIES

PHYSICS 1 - SERIES 14

131/01

TIME: 2:30 HRS

JANUARY-MAY, 2023

INSTRUCTIONS

1. This paper consists of two sections A and B.
2. Answer nine (9) questions, choosing ALL questions from sections A and only two (2) questions from section B.
3. Mathematical tables and non-programmable calculators may be used.
4. Any unauthorized materials are not allowed in the examination room.
5. Write your examination number on your answer booklet(s) on every page.

The following information may be useful:

• Thermal conductivity of plaster = \(0.60 \text{W} m^{-1} k^{-1}\)
• Thermal conductivity of fiberglass = \(0.040 \text{W} m^{-1} k^{-1}\)
• Acceleration due to gravity, \(g = 9.8 \text{m/s}^2\)
• The radius of the earth = \(6.38 \times 10^6 \text{m}\)
• Mass of the earth = \(5.98 \times 10^{24} kg\)
• Universal gravitational constant = \(6.67 \times 10^{-11} \text{N} m^2 kg^{-2}\)
• Heat of vaporization of water = \(2256 \times 10^3 \text{J/kg}\)
• 1 atm = \(1.01 \times 10^5 Pa\)
• Pie, \(\pi = 3.14\)
• Density of air = \(1.3 \, \text{kg/m}^3\)
• Electronic charge, e = \(1.6 \times 10^{-19} \, \text{C}\)
• Thermal conductivity of ice = \(2.3 \, \text{Wm}^{-1} \text{K}^{-1}\)
• Molar gas constant is \(8.31 \, \text{Jmol}^{-1} \text{K}^{-1}\)

Page 1 of 6

SECTION A: (70 Marks)
Answer ALL questions from this section

1. (a) (i) (01 mark)

Define the term dimension of a physical quantity.

(ii) (02 marks)

Show that the expression \( V = V_0 + at \) is dimensionally correct, where \( V \) and \( V_0 \) represent velocities, 'a' is acceleration and t is a time interval.

(b) (i) (01 mark)

What are the basic rules of dimensional analysis?

(ii) (02.5 marks)

A gas bubble from an explosion under water oscillates with period T proportional to \( P^a d^b E^c \) where 'P' is the static pressure, 'd' is the density of water and 'E' is the total energy of the explosion. Find the values of a, b and c.

(c) (i) (01 mark)

What is meant by Absolute Error?

(ii) (02.5 marks)

The period of oscillation of a simple pendulum in an experiment is recorded as 2.63s, 2.56s, 2.42s, 2.71s and 2.80s respectively. Find the mean time period, absolute error in each observation and percentage error.

2. (a) (i) (02 marks)

Explain why a horse cannot pull a cart and run in empty space?

(ii) (02.5 marks)

A man of 90kg jumps into a swimming pool from a height of 5m. If it takes 0.4 seconds for the water in a pool to reduce its velocity to zero, what average force did the water exert on the man?

(b) (i) (02.5 marks)

An object at rest explodes into three pieces of equal masses. One moves east at 20m/s, a second moves south-east at 30m/s. What is the velocity of the third piece?

(ii) (03 marks)

A block is released from rest from a height of 1m on a 45° rough inclined surface. It comes to rest after covering 1.8m on the horizontal part of the surface. Find the coefficient of friction between the block and the surface.

Page 2 of 6

3. (a) (02 marks)

What do you understand by the following terms:

i. Oscillation

ii. Simple harmonic motion

(b) (04 marks)

If the displacement of N is given by \( x = r \cos \theta \) and \( \theta = \omega t \), Sketch the graph of the following components:

(i) Showing the variation of the displacement of N with time

(ii) Showing the variation of the velocity of N with time

(iii) Showing the variation of the acceleration of N with time

(iv) From the graphs, obtain the phase difference present between the velocity and the acceleration

(c) (04 marks)

A simple pendulum has a period of 2.0s and an amplitude of swing 5.0cm. Calculate the maximum magnitudes of:

(i) The velocity of the bob

(ii) The acceleration of the bob

4. (a) (i) (01 mark)

Define the term angular momentum.

(ii) (02.5 marks)

A shaft rotating at \(3.0 \times 10^3\) revolutions per minute is transmitting a power of 10 Kilowatts. Find the magnitude of driving couple.

(b) (i) (01.5 marks)

State the Newton Law of universal gravitation.

(ii) (02 marks)

A satellite of mass M moves in circular orbit about the Earth with a constant speed of V and a height of \(h = 1000km\) above the Earth's surface. Find the orbital speed of satellite.

(c) (03 marks)

A rocket is launched vertically upward from the surface of the earth with an initial velocity of \(V_0\). Show that its velocity V at a height h is given by:

\[V_0^2 - V^2 = \frac{2gh}{1+\frac{h}{R}}\]

where R is the radius of the earth and g is the acceleration due to gravity at the earth's surface.

4. (a) (i) (01 mark)

Briefly explain why there is no unique value of moment of inertia of a given body.

(ii) (01 mark)

If polar ice caps melts and spread uniformly, how will the length of the day be affected?

(iii) (03 marks)

A mass of 0.3kg hangs from the rim of a wheel of radius 0.1cm by a light string which is wound round the wheel. When released from rest, the mass falls through a distance of 5m in 10 seconds rotating the wheel. Find the moment of inertia of the wheel.

(b) (i) (02 marks)

With what velocity must a body be thrown upwards from the surface of the earth so that it reaches a height of 10R (R is the radius of the earth)?

(ii) (03 marks)

A satellite in stable orbit contains two closed vessels one of these is filled with water while the other is filled with hot steam. Explain why the water exerts very little pressure on its container but steam exerts almost the same pressure as it would on earth when at the same temperature.

Page 3 of 6

5. (a) (i) (01 mark)

What is meant by adiabatic process?

(ii) (01 mark)

Are melting and boiling isothermal changes?

(b) (04 marks)

Let 1.0kg of liquid water of \(100^\circ C\) be converted to steam at \(100^\circ C\) by boiling at standard atmospheric pressure. The volume of that water changes from an initial value of \(1.0 \times 10^{-3} m^3\) as a liquid to \(1.671 m^3\) as steam.

(i) How much work is done by the system during this process?

(ii) How much energy is transferred as heat during the process?

(c) (i) (02 marks)

Explain why a gas has two specific heats where as a liquid and solid have only one.

(ii) (02 marks)

Use the first law of thermodynamics, explain why the specific latent heat of vaporisation is greater than the specific latent heat of fusion for a particular substance.

6. (a) (i) (02 marks)

Why do two layers of cloth of equal thickness provide warmer covering than a single layer of cloth of double the thickness?

(ii) (03 marks)

Explain why, the cooling unit of a refrigerator is fitted near the top.

(b) (05 marks)

One face of a sheet of cork 3mm thick is placed in contact with a glass sheet 5mm thick, both sheets being 20cm square. The outer face of this square composite sheet is maintained at \(100^\circ C\) and \(20^\circ C\), the cork being at higher temperature. Find the temperature of Glass-cork interface. Given, the thermal conductivity of cork = \(6.3 \times 10^{-2} Wm^{-1} K^{-1}\) and thermal conductivity of glass = \(7.2 \times 10^{-1} Wm^{-1} K^{-1}\).

7. (a) (i) (01 mark)

What is meant by aerial environment? Give two examples.

(ii) (02 marks)

Describe three ways at which the aerial environment is threatened.

(b) (i) (02 marks)

Describe the importance of shading, mulching and sheltering in agriculture.

(ii) (02 marks)

Describe the four major components of soil.

(c) (03 marks)

Explain the formation of an earth quake using the elastic rebound theory.

Page 4 of 6

SECTION B: (30 Marks)
Answer any two (02) questions from this section

8. (a) (i) (03 marks)

Explain why, when a current is taken from a battery, the reading given by a high resistance voltmeter connected across the battery terminals decreases as current taken increases.

(ii) (02 marks)

Under what condition is the heat produced in an electric circuit inversely proportional to resistance?

(b) (i) (03 marks)

A storage battery of electromotive force of 8.0V and internal resistance 0.5Ω is being charged by a 120V d.c supply using a series resistor of 15.5Ω.

What is the terminal voltage of the battery during charging?

(ii) (03 marks)

What is the purpose of having a series resistor in the charging circuit?

(c) (04 marks)

Which is more dangerous between an electric shock suffered from an a.c source or a d.c source rated at the same voltage? Give two reasons to support your answer.

9. (a) (i) (04 marks)

Define the term OPAMP stating its three important characteristics.

(ii) (03 marks)

Give three advantages of negative feedback to an OPAMP.

(b) (i) (03 marks)

Show that, the closed loop gain of the non-inverting amplifier with negative feedback is given by

\[A_{v} = 1 + \frac{R_f}{R_1}\]

where each letter carries its usual meaning.

(c) (05 marks)

Calculate output voltage in the following OPAMP circuit.

90kΩ
12V
10
3
10kΩ
Vout

Page 5 of 6

10. (a) (i) (02 marks)

Why are integrated circuits more reliable?

(ii) (03 marks)

Explain how OR gate is realised using NAND gate.

(b) (06 marks)

The Attorney general is to elected by the majority voting system for three judges A, B and C. Each judge presses a switch for a Yes vote causing the respective input to rise to logic state 1. However, the seniority judge is to be considered, whereby the most senior judge C has weighted vote equivalent to four votes of the junior judge A. The senior judge B's vote is taken to be three votes of the junior judge A. If the majority YES vote will be passed only when the vote, in favour, exceeds half of the total points, (assume the junior judge casts a vote of 1 point equivalent) then;

(i) Determine the truth table defining the variables,

(ii) Deduce the simplified Boolean expression for the problem.

(iii) Design the circuit including logic gates.

(c) (i) (02 marks)

Distinguish between "Frequency Modulated" and "Amplitude Modulated" radio waves.

(ii) (02 marks)

Explain why FM radio broadcasting is currently more preferred than AM radio broadcasting.

Page 6 of 6

UMOJA WA WAZAZI TANZANA

WARI SECONDARY SCHOOL

PRE-NATIONAL EXAMINATION SERIES

PHYSICS 1 - SERIES 14

131/01

TIME: 2:30 HRS

JANUARY-MAY, 2023

Instructions

1. This paper consists of two sections A and B.
2. Answer nine (9) questions, choosing ALL questions from sections A and only two (2) questions from section B.
3. Mathematical tables and non-programmable calculators may be used.
4. Any unauthorized materials are not allowed in the examination room.
5. Write your examination number on your answer booklet(s) on every page.

Useful Information

• Thermal conductivity of plaster = \(0.60 \text{W} m^{-1} k^{-1}\)
• Thermal conductivity of fiberglass = \(0.040 \text{W} m^{-1} k^{-1}\)
• Acceleration due to gravity, \(g = 9.8 \text{m/s}^2\)
• The radius of the earth = \(6.38 \times 10^6 \text{m}\)
• Mass of the earth = \(5.98 \times 10^{24} kg\)
• Universal gravitational constant = \(6.67 \times 10^{-11} \text{N} m^2 kg^{-2}\)
• Heat of vaporization of water = \(2256 \times 10^3 \text{J/kg}\)
• 1 atm = \(1.01 \times 10^5 Pa\)
• Pie, \(\pi = 3.14\)
• Density of air = \(1.3 \, \text{kg/m}^3\)
• Electronic charge, e = \(1.6 \times 10^{-19} \, \text{C}\)
• Thermal conductivity of ice = \(2.3 \, \text{Wm}^{-1} \text{K}^{-1}\)
• Molar gas constant is \(8.31 \, \text{Jmol}^{-1} \text{K}^{-1}\)

SECTION A (70 Marks)

Answer ALL questions from this section

1. (a) (i)

01 mark

Define the term dimension of a physical quantity.

1. (a) (ii)

02 marks

Show that the expression \( V = V_0 + at \) is dimensionally correct, where \( V \) and \( V_0 \) represent velocities, 'a' is acceleration and t is a time interval.

1. (b) (i)

01 mark

What are the basic rules of dimensional analysis?

1. (b) (ii)

02.5 marks

A gas bubble from an explosion under water oscillates with period T proportional to \( P^a d^b E^c \) where 'P' is the static pressure, 'd' is the density of water and 'E' is the total energy of the explosion. Find the values of a, b and c.

1. (c) (i)

01 mark

What is meant by Absolute Error?

1. (c) (ii)

02.5 marks

The period of oscillation of a simple pendulum in an experiment is recorded as 2.63s, 2.56s, 2.42s, 2.71s and 2.80s respectively. Find the mean time period, absolute error in each observation and percentage error.

2. (a) (i)

02 marks

Explain why a horse cannot pull a cart and run in empty space?

2. (a) (ii)

02.5 marks

A man of 90kg jumps into a swimming pool from a height of 5m. If it takes 0.4 seconds for the water in a pool to reduce its velocity to zero, what average force did the water exert on the man?

2. (b) (i)

02.5 marks

An object at rest explodes into three pieces of equal masses. One moves east at 20m/s, a second moves south-east at 30m/s. What is the velocity of the third piece?

2. (b) (ii)

03 marks

A block is released from rest from a height of 1m on a 45° rough inclined surface. It comes to rest after covering 1.8m on the horizontal part of the surface. Find the coefficient of friction between the block and the surface.

Comprehensive Answers

Question 1 Answers

1. (a) (i) Definition of dimension of a physical quantity:

The dimension of a physical quantity is the expression that shows how it is related to the fundamental quantities (mass, length, time, etc.). Dimensions represent the nature of a physical quantity and are independent of its magnitude. For example, the dimension of velocity is [LT⁻¹], which means it is derived from length divided by time.

1. (a) (ii) Dimensional correctness of \( V = V_0 + at \):

To check dimensional correctness, we analyze the dimensions of each term:

Left-hand side: V (velocity) has dimensions [LT⁻¹]

Right-hand side:

• V₀ (velocity) has dimensions [LT⁻¹]
• a (acceleration) has dimensions [LT⁻²]
• t (time) has dimensions [T]
• Therefore, at has dimensions [LT⁻²] × [T] = [LT⁻¹]

Since all terms have the same dimensions [LT⁻¹], the equation is dimensionally correct.

1. (b) (i) Basic rules of dimensional analysis:

1. Principle of homogeneity: All terms in a physical equation must have the same dimensions.
2. Dimensionless quantities: Quantities like angles, trigonometric functions, and exponential functions are dimensionless.
3. Addition and subtraction: Only quantities with the same dimensions can be added or subtracted.
4. Multiplication and division: Dimensions are multiplied or divided when quantities are multiplied or divided.

1. (b) (ii) Finding a, b, and c for T ∝ PᵃdᵇEᶜ:

Given: T ∝ PᵃdᵇEᶜ

Dimensions:

• T (time) = [T]
• P (pressure) = [ML⁻¹T⁻²]
• d (density) = [ML⁻³]
• E (energy) = [ML²T⁻²]

Equating dimensions:

[T] = [ML⁻¹T⁻²]ᵃ × [ML⁻³]ᵇ × [ML²T⁻²]ᶜ

[T] = [Mᵃ⁺ᵇ⁺ᶜ L⁻ᵃ⁻³ᵇ⁺²ᶜ T⁻²ᵃ⁻²ᶜ]

Equating powers:

• For M: a + b + c = 0
• For L: -a - 3b + 2c = 0
• For T: -2a - 2c = 1

Solving these equations:

From T: -2a - 2c = 1 ⇒ a + c = -½

From M: b = -a - c = ½

From L: -a - 3(½) + 2c = 0 ⇒ -a + 2c = 1.5

Solving: a = -5/6, b = ½, c = 1/3

Therefore: a = -5/6, b = ½, c = 1/3

1. (c) (i) Absolute Error:

Absolute error is the magnitude of the difference between the measured value and the true value of a quantity. It represents the actual error in a measurement without considering the size of the quantity being measured. For example, if the true length is 10.0 cm and you measure it as 10.2 cm, the absolute error is 0.2 cm.

1. (c) (ii) Calculations for pendulum experiment:

Observations: 2.63s, 2.56s, 2.42s, 2.71s, 2.80s

Mean time period:

T_mean = (2.63 + 2.56 + 2.42 + 2.71 + 2.80) / 5 = 13.12 / 5 = 2.624 s

Absolute errors:

• ΔT₁ = |2.63 - 2.624| = 0.006 s
• ΔT₂ = |2.56 - 2.624| = 0.064 s
• ΔT₃ = |2.42 - 2.624| = 0.204 s
• ΔT₄ = |2.71 - 2.624| = 0.086 s
• ΔT₅ = |2.80 - 2.624| = 0.176 s

Mean absolute error:

ΔT_mean = (0.006 + 0.064 + 0.204 + 0.086 + 0.176) / 5 = 0.536 / 5 = 0.1072 s

Percentage error:

Percentage error = (ΔT_mean / T_mean) × 100% = (0.1072 / 2.624) × 100% = 4.09%

Question 2 Answers

2. (a) (i) Why a horse cannot pull a cart in empty space:

A horse cannot pull a cart and run in empty space due to the absence of friction. According to Newton's third law of motion, when the horse pulls the cart, it exerts a force on the ground backward. The ground, in turn, exerts an equal and opposite forward force (friction) on the horse's hooves, which enables the horse to move forward and pull the cart.

In empty space, there is no medium (like ground) to provide this reaction force. Without this external force to push against, the horse and cart system would not be able to accelerate or move in any particular direction, regardless of how hard the horse pulls.

2. (a) (ii) Average force exerted by water on the man:

Given:

• Mass of man, m = 90 kg
• Height, h = 5 m
• Time to stop, t = 0.4 s

Velocity just before hitting water:

v = √(2gh) = √(2 × 9.8 × 5) = √98 = 9.9 m/s

Deceleration in water:

a = Δv / t = (0 - 9.9) / 0.4 = -24.75 m/s²

Average force exerted by water:

F = m × a = 90 × 24.75 = 2227.5 N

The average force exerted by water on the man is 2227.5 N.

2. (b) (i) Velocity of the third piece after explosion:

Let the mass of each piece be m.

Initial momentum = 0 (object at rest)

Let's define directions:

• East: +x direction
• North: +y direction

First piece: v₁ = 20 m/s east ⇒ p₁ = (20m, 0)

Second piece: v₂ = 30 m/s southeast (45° south of east)

Components: v₂ₓ = 30 cos 45° = 21.21 m/s

v₂ᵧ = -30 sin 45° = -21.21 m/s (negative for south)

p₂ = (21.21m, -21.21m)

By conservation of momentum:

p₁ + p₂ + p₃ = 0

p₃ = -p₁ - p₂ = (-20m - 21.21m, 0 + 21.21m) = (-41.21m, 21.21m)

Velocity of third piece:

v₃ₓ = -41.21 m/s, v₃ᵧ = 21.21 m/s

Magnitude: v₃ = √(41.21² + 21.21²) = √(1698.3 + 449.9) = √2148.2 = 46.35 m/s

Direction: θ = tan⁻¹(21.21 / 41.21) = tan⁻¹(0.5146) = 27.2° north of west

The third piece moves at 46.35 m/s at 27.2° north of west.

2. (b) (ii) Coefficient of friction:

Given:

• Height on incline, h = 1 m
• Angle of incline, θ = 45°
• Distance on horizontal, s = 1.8 m

Velocity at bottom of incline:

Using conservation of energy:

mgh = ½mv² ⇒ v = √(2gh) = √(2 × 9.8 × 1) = √19.6 = 4.43 m/s

On horizontal surface:

Initial velocity, u = 4.43 m/s

Final velocity, v = 0

Distance, s = 1.8 m

Using v² = u² + 2as:

0 = (4.43)² + 2a(1.8)

0 = 19.62 + 3.6a

a = -19.62 / 3.6 = -5.45 m/s²

Friction force:

F = ma = m × 5.45

Also, F = μN = μmg

μmg = m × 5.45

μ = 5.45 / 9.8 = 0.556

The coefficient of friction is 0.556.

Question 3 Answers

3. (a) Definitions:

i. Oscillation: Oscillation is the repetitive variation, typically in time, of some measure about a central value or between two or more different states. It refers to any motion that repeats itself in equal intervals of time.

ii. Simple Harmonic Motion (SHM): Simple Harmonic Motion is a special type of oscillatory motion in which the restoring force is directly proportional to the displacement from the mean position and acts in the direction opposite to that of displacement. The motion is sinusoidal in time and demonstrates a single resonant frequency.

3. (b) Graphs for SHM:

Given: x = r cos θ, θ = ωt ⇒ x = r cos(ωt)

(i) Displacement vs time: A cosine curve starting at maximum amplitude r at t=0, oscillating between +r and -r.

(ii) Velocity vs time: v = dx/dt = -rω sin(ωt). A sine curve phase-shifted by 90° from displacement.

(iii) Acceleration vs time: a = dv/dt = -rω² cos(ωt). A cosine curve phase-shifted by 180° from displacement.

(iv) Phase difference: Velocity leads displacement by 90° (π/2 radians). Acceleration leads velocity by 90° (π/2 radians). Therefore, acceleration and velocity have a phase difference of 90°.

3. (c) Simple pendulum calculations:

Given: T = 2.0 s, A = 5.0 cm = 0.05 m

Angular frequency:

ω = 2π/T = 2π/2 = π rad/s

(i) Maximum velocity:

v_max = Aω = 0.05 × π = 0.157 m/s

(ii) Maximum acceleration:

a_max = Aω² = 0.05 × π² = 0.05 × 9.87 = 0.4935 m/s²

WARI SECONDARY SCHOOL - PRE-NATIONAL EXAMINATION SERIES

PHYSICS 1 - SERIES 14 | 131/01

NECTA Form Six Biology 1 Examination Guide

Comprehensive resource covering cell biology, genetics, physiology, and ecology with detailed solutions to common examination questions

Examination Code: 051

Introduction to Biology 1 Examination

The National Examinations Council of Tanzania (NECTA) Form Six Biology 1 examination is a fundamental component of the Advanced Certificate of Secondary Education Examination (ACSEE). Biology 1 focuses on fundamental biological principles including cell biology, genetics, physiology, and ecology, forming the foundation for advanced biological studies.

Examination Format: The Biology 1 paper consists of two sections: Section A with 10 compulsory short answer questions (40 marks), and Section B with 4 essay questions where candidates choose 3 (60 marks). The total examination time is 3 hours, carrying 100 marks total. Emphasis is placed on understanding biological processes, diagrams, and application of biological principles.

Biology 1 requires mastery of both theoretical concepts and practical applications. Success in this examination depends on understanding biological processes, interpreting diagrams, and applying knowledge to solve biological problems.

Examination Structure

The Biology 1 paper is systematically organized to assess knowledge, understanding, and application of biological principles:

A SECTION A: SHORT ANSWER QUESTIONS

Total Marks: 40 | Time Allocation: 60 minutes

This section tests broad knowledge across the entire syllabus with 10 compulsory questions covering various topics.

Cell Biology: 12-15 marks Genetics: 10-12 marks Physiology: 8-10 marks Ecology: 7-10 marks

B SECTION B: ESSAY QUESTIONS

Total Marks: 60 | Time Allocation: 120 minutes

Candidates choose 3 out of 4 questions, each carrying 20 marks. Questions typically require detailed explanations, diagrams, and problem-solving.

Process Explanation: 25-35 marks Diagram Drawing: 15-20 marks Problem Solving: 10-15 marks

Important: The examination places significant emphasis on biological diagrams and process explanations. Approximately 30-40% of the total marks involve drawing and labeling diagrams or explaining biological processes step-by-step.

Biology 1 Topics and Content

The Biology 1 syllabus covers fundamental areas of biology essential for understanding living organisms:

1. Cell Biology

• Cell structure and ultrastructure
• Cell organelles and their functions
• Cell membrane structure and transport
• Cell division: mitosis and meiosis
• Cellular respiration and photosynthesis
• Enzymes and metabolic pathways

2. Genetics

• Structure and function of DNA and RNA
• Protein synthesis: transcription and translation
• Mendelian genetics and inheritance patterns
• Genetic crosses and Punnett squares
• Mutations and genetic disorders
• Genetic engineering and biotechnology

3. Physiology

• Nutrition and digestion in mammals
• Respiration and gas exchange
• Transport systems: blood circulation
• Excretion and osmoregulation
• Nervous coordination and hormones
• Homeostasis and feedback mechanisms

4. Plant Biology

• Plant tissue organization
• Photosynthesis and plant nutrition
• Transport in plants: xylem and phloem
• Plant growth and development
• Plant hormones and responses
• Reproduction in flowering plants

5. Ecology

• Ecosystem structure and function
• Energy flow and nutrient cycling
• Population dynamics and growth
• Community interactions
• Conservation and biodiversity
• Human impact on ecosystems

6. Microbiology

• Classification of microorganisms
• Bacterial structure and reproduction
• Viruses: structure and replication
• Fungi: structure and importance
• Microbial diseases and control
• Role of microbes in ecosystems

7. Evolution

• Theories of evolution
• Natural selection and adaptation
• Evidence for evolution
• Speciation and isolation mechanisms
• Human evolution
• Origin of life theories

8. Practical Biology

• Microscopy techniques
• Biological drawing rules
• Experimental design and variables
• Data collection and analysis
• Biological techniques
• Safety in biology laboratory

Key Process: DNA → RNA → Protein (Central Dogma of Molecular Biology)

NECTA Examination Objectives

NECTA designs the Biology 1 examination to assess specific competencies aligned with the Tanzanian curriculum. The examination aims to evaluate students' ability to:

Knowledge and Understanding

Biological Concepts

Recall and explain fundamental biological concepts, principles, and theories across all topics in the syllabus.

Process Comprehension

Understand biological processes such as photosynthesis, respiration, protein synthesis, and genetic inheritance.

Structural Knowledge

Identify and describe biological structures at cellular, tissue, organ, and system levels.

Application and Analysis

• Problem Solving: Apply biological principles to solve genetics problems and ecological scenarios
• Data Interpretation: Analyze and interpret data from experiments, graphs, and tables
• Process Explanation: Explain biological processes step-by-step with correct terminology
• Real-world Application: Apply biological knowledge to health, agriculture, and environmental issues

Practical Skills

• Diagram Drawing: Draw and label accurate biological diagrams
• Experimental Design: Design experiments to test biological hypotheses
• Observation Skills: Make accurate biological observations and recordings
• Measurement Techniques: Use biological measuring instruments correctly

Scientific Communication

• Scientific Explanation: Explain biological phenomena using appropriate terminology
• Diagram Interpretation: Interpret and explain biological diagrams
• Logical Presentation: Present biological information in logical sequence
• Terminology Usage: Use correct biological terms and avoid ambiguity

Examination Focus: The Biology 1 paper emphasizes process understanding and diagram skills—not just memorization of facts. Understanding biological processes and being able to draw and interpret diagrams are crucial for success.

Common Examination Questions with Detailed Solutions

Based on analysis of previous NECTA Biology 1 examinations, here are frequently tested question types with model solutions:

1 Cell Biology: Structure and Function

Typical Question: "Draw and label a diagram of an animal cell as seen under an electron microscope. State the functions of: (a) Mitochondria, (b) Rough endoplasmic reticulum, (c) Golgi apparatus, (d) Nucleus."

Solution Strategy

Animal Cell Diagram (Electron Microscope View)

Note: In examination, draw a large, clear diagram with these labeled structures:

Key structures to include in diagram:

• Cell membrane (plasma membrane)
• Nucleus with nuclear envelope and nucleolus
• Mitochondria (show cristae and matrix)
• Endoplasmic reticulum (rough and smooth)
• Golgi apparatus (stack of cisternae)
• Ribosomes (free and attached)
• Lysosomes
• Cytoplasm

Functions of organelles:

(a) Mitochondria:
• Site of aerobic respiration (Krebs cycle and electron transport chain)
• Produce ATP (energy currency of the cell)
• Have their own DNA and ribosomes (semi-autonomous)
• Cristae increase surface area for respiratory enzymes

(b) Rough Endoplasmic Reticulum:
• Studded with ribosomes on cytoplasmic surface
• Site of protein synthesis and modification
• Transports proteins to Golgi apparatus
• Forms transport vesicles

(c) Golgi Apparatus:
• Modifies, sorts, and packages proteins from ER
• Forms lysosomes and secretory vesicles
• Adds carbohydrates to proteins to form glycoproteins
• Produces polysaccharides for cell walls (in plants)

(d) Nucleus:
• Contains genetic material (DNA)
• Controls cell activities through gene expression
• Site of DNA replication and transcription
• Contains nucleolus for ribosome synthesis

Key Points: Draw with sharp pencil, label with straight lines, no arrowheads, labels on right side. Functions should be precise and use correct biological terminology.

2 Genetics: Inheritance Patterns

Typical Question: "In humans, brown eyes (B) are dominant over blue eyes (b). A brown-eyed man whose father had blue eyes marries a blue-eyed woman. What are the possible genotypes and phenotypes of their children? Show your working using a genetic diagram."

Solution Strategy

Step 1: Determine parental genotypes

Man: Brown eyes but father had blue eyes (bb)
Therefore man must be heterozygous: Bb (if he was BB, he couldn't have a blue-eyed father)
Woman: Blue eyes must be homozygous recessive: bb

Step 2: Set up genetic cross

Punnett Square:

	b	b
B	Bb	Bb
b	bb	bb

Step 3: Analyze results

Genotypic ratio: 2 Bb : 2 bb or 1:1 ratio
Phenotypic ratio: 2 Brown eyes : 2 Blue eyes or 1:1 ratio

Possible genotypes of children: Bb or bb
Possible phenotypes of children: Brown eyes or Blue eyes

Probability:
• Brown-eyed child: 50% (1/2)
• Blue-eyed child: 50% (1/2)

Key Points: Always show working with clear genetic diagrams. Remember that if a dominant trait individual has a recessive parent, they must be heterozygous. Use proper genetic notation (capital for dominant, lowercase for recessive).

3 Physiology: Photosynthesis

Typical Question: "Describe the process of photosynthesis, including: (a) The raw materials and products, (b) The two main stages (light-dependent and light-independent reactions), (c) The importance of photosynthesis in ecosystems."

Solution Strategy

(a) Raw Materials and Products:

Overall equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂

Raw materials: Carbon dioxide (CO₂), Water (H₂O), Light energy
Products: Glucose (C₆H₁₂O₆), Oxygen (O₂)
Site: Chloroplasts in plant cells

(b) Two Main Stages:

1. Light-Dependent Reactions (Photolysis):
• Location: Thylakoid membranes of chloroplasts
• Requirements: Light, water, chlorophyll, ADP, NADP⁺
• Process:
  - Light energy absorbed by chlorophyll
  - Photolysis of water: 2H₂O → 4H⁺ + 4e⁻ + O₂
  - ATP formed from ADP + Pi (photophosphorylation)
  - NADPH formed from NADP⁺ + H⁺ + 2e⁻
• Products: ATP, NADPH, O₂ (byproduct)
• Oxygen released into atmosphere

2. Light-Independent Reactions (Calvin Cycle):
• Location: Stroma of chloroplasts
• Requirements: CO₂, ATP, NADPH
• Process:
  - CO₂ fixation: CO₂ combines with RuBP (5C) to form 2 molecules of GP (3C)
  - Reduction: GP reduced to TP using ATP and NADPH
  - Regeneration: Most TP used to regenerate RuBP
  - Some TP used to make glucose and other organic compounds
• Products: Glucose, other carbohydrates, regenerated RuBP

(c) Importance in Ecosystems:

1. Primary Production: Converts light energy to chemical energy stored in glucose
2. Oxygen Production: Releases O₂ essential for aerobic respiration
3. Carbon Fixation: Removes CO₂ from atmosphere, reduces greenhouse effect
4. Food Source: Produces organic compounds that form basis of food chains
5. Energy Flow: Transfers solar energy to biological systems
6. Biochemical Basis: Provides organic molecules for biosynthesis

Key Points: Memorize the overall equation. Understand that light reactions produce ATP and NADPH for dark reactions. Dark reactions don't require light but use products of light reactions.

4 Ecology: Energy Flow

Typical Question: "Describe how energy flows through an ecosystem, including: (a) Trophic levels, (b) Energy transfer efficiency, (c) Pyramid of energy. Explain why food chains rarely have more than four or five trophic levels."

Solution Strategy

(a) Trophic Levels:

1. Producers (Autotrophs): Plants, algae, phytoplankton - convert solar energy to chemical energy via photosynthesis
2. Primary Consumers (Herbivores): Feed directly on producers
3. Secondary Consumers (Carnivores): Feed on primary consumers
4. Tertiary Consumers: Feed on secondary consumers
5. Quaternary Consumers: Top carnivores
6. Decomposers: Break down dead organic matter (bacteria, fungi)

(b) Energy Transfer Efficiency:

• Only about 10% of energy is transferred from one trophic level to the next
• 90% of energy is lost at each transfer due to:
  - Heat loss from respiration
  - Not all biomass consumed
  - Not all consumed biomass digested
  - Energy used for movement, reproduction, etc.

Example: If producers have 10,000 kJ energy:
• Primary consumers get: 1,000 kJ (10%)
• Secondary consumers get: 100 kJ (10% of 1,000)
• Tertiary consumers get: 10 kJ (10% of 100)

(c) Pyramid of Energy:

• Graphical representation of energy flow
• Always upright (broad base, narrow top)
• Measured in kJ/m²/year
• Each level represents energy content of that trophic level
• Shows rapid decrease in available energy at higher levels

Why food chains are short (rarely >5 levels):

1. Energy Limitation: After 4-5 transfers, insufficient energy remains to support another level
2. 10% Rule: With only 10% transfer efficiency, energy becomes too limited
3. Biomass Constraint: Higher levels require large areas to support few individuals
4. Evolutionary Factors: Longer chains less stable and more prone to disruption
5. Size Considerations: Top predators need to be large enough to capture prey
6. Efficiency Trade-off: More levels mean less energy for top consumers

Key Points: Remember the 10% rule. Energy pyramids are always upright. Energy flows linearly through ecosystems and is not recycled (unlike nutrients).

Essential Biology 1 Concepts and Processes

Cell Biology

Genetics

Physiology

Ecology

Key Cell Biology Concepts

Prokaryotic vs Eukaryotic

Organelle Functions

Cell Membrane Transport

Mitosis & Meiosis

Enzyme Action

Cellular Respiration

Photosynthesis

Protein Synthesis

Mitosis vs Meiosis:
• Mitosis: 1 division → 2 identical diploid cells (growth, repair)
• Meiosis: 2 divisions → 4 genetically different haploid cells (gamete formation)

Aerobic vs Anaerobic Respiration:
• Aerobic: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 36 ATP (with oxygen)
• Anaerobic (animals): C₆H₁₂O₆ → 2C₃H₆O₃ + 2 ATP (lactic acid)
• Anaerobic (plants/yeast): C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂ + 2 ATP (ethanol)

Key Genetics Concepts

DNA Structure

Protein Synthesis

Mendelian Genetics

Punnett Squares

Genetic Crosses

Mutations

Genetic Engineering

Pedigree Analysis

Central Dogma of Molecular Biology:
DNA → Transcription → RNA → Translation → Protein

Types of Inheritance:
1. Complete Dominance: One allele completely masks another
2. Incomplete Dominance: Heterozygous shows intermediate phenotype
3. Co-dominance: Both alleles expressed equally (e.g., AB blood type)
4. Sex-linked: Genes on X chromosome (e.g., color blindness)
5. Multiple Alleles: More than 2 alleles exist (e.g., ABO blood groups)

Key Physiology Concepts

Digestive System

Respiratory System

Circulatory System

Excretory System

Nervous System

Endocrine System

Homeostasis

Plant Physiology

Human Digestive System Key Enzymes:
• Mouth: Salivary amylase (starch → maltose)
• Stomach: Pepsin (proteins → peptides), HCl (acidic pH)
• Duodenum: Trypsin, lipase, pancreatic amylase
• Small Intestine: Maltase, lactase, sucrase, peptidases

Homeostasis Mechanisms:
• Blood Glucose: Insulin (lowers), Glucagon (raises)
• Body Temperature: Sweating, vasodilation/constriction
• Water Balance: ADH (anti-diuretic hormone)
• Calcium Levels: Parathyroid hormone, Calcitonin

Key Ecology Concepts

Ecosystem Structure

Energy Flow

Nutrient Cycles

Population Dynamics

Community Interactions

Succession

Biodiversity

Conservation

Nutrient Cycles:
1. Carbon Cycle: Photosynthesis, respiration, combustion, decomposition
2. Nitrogen Cycle: Nitrogen fixation, nitrification, denitrification, ammonification
3. Water Cycle: Evaporation, transpiration, condensation, precipitation

Types of Ecological Pyramids:
1. Pyramid of Numbers: Number of organisms at each level
2. Pyramid of Biomass: Dry mass at each level (usually upright)
3. Pyramid of Energy: Energy content at each level (always upright)

Practical Biology and Laboratory Work

Microscopy Skills

• Setting up and using light microscope
• Preparing temporary mounts
• Biological drawing rules
• Measuring microscopic objects
• Staining techniques

Physiological Experiments

• Testing for food substances
• Enzyme activity experiments
• Respiration rate measurements
• Photosynthesis experiments
• Heart rate and exercise experiments

Ecological Studies

• Quadrant sampling techniques
• Population estimation methods
• Measuring abiotic factors
• Food chain analysis
• Biodiversity calculations

Important: Always Follow in Examinations

• Draw diagrams with sharp pencil, no shading
• Use clear, straight labeling lines
• Label on right side of diagram
• Include magnification when required
• Write titles for all diagrams

Examination Preparation Strategies

Time Management During Examination

• Section A (60 minutes): Approximately 6 minutes per question (10 questions)
• Section B (120 minutes): 40 minutes per essay question (3 questions)
• Planning Time: First 5 minutes to read through paper and plan approach
• Diagram Time: Allocate 5-10 minutes for each required diagram
• Review Time: Reserve 15 minutes at end for checking diagrams and labels

Effective Study Techniques for Biology 1

Diagram Practice

• Practice drawing biological diagrams regularly
• Learn labeling conventions
• Memorize key structures for each system
• Practice under timed conditions

Process Understanding

• Create flowcharts for biological processes
• Explain processes in your own words
• Connect different biological systems
• Understand rather than memorize processes

Terminology Mastery

• Create flashcards for biological terms
• Practice using terms in explanations
• Learn Latin/Greek roots of biological terms
• Understand precise meanings of terms

Common Mistakes to Avoid

• Poor diagrams: Always use pencil, draw large, label clearly
• Incomplete labeling: Label all required structures
• Wrong terminology: Use correct biological terms
• Oversimplifying processes: Include all key steps in process descriptions
• Confusing similar terms: Distinguish clearly between similar concepts
• Missing units: Include units in measurements and calculations
• Incomplete genetic diagrams: Show all steps in genetic crosses
• Ignoring application: Relate biological concepts to real-world situations

Additional Resources and References

Recommended Textbooks

• "Biology for Advanced Level" by Glenn and Susan Toole
• "Advanced Biology" by Michael Kent
• "Cambridge International AS & A Level Biology" by Mary Jones
• "Biology" by Campbell and Reece
• "Principles of Biology" by Robert J. Brooker
• Tanzanian Institute of Education (TIE) Biology 1 textbooks

NECTA-Specific Resources

• NECTA Past Papers: Minimum 5 years of past papers with marking schemes
• Examiners' Reports: Analyze common mistakes highlighted by examiners
• Syllabus: Official NECTA Biology 1 syllabus for Form V-VI
• Practical Guides: Laboratory manuals for Biology 1 experiments

Online Learning Resources

• Khan Academy Biology sections
• Biology animation websites for processes
• Virtual biology laboratories
• YouTube channels for biology tutorials
• Interactive biology diagrams and quizzes

Final Advice: Biology 1 success requires systematic study of biological processes and regular diagram practice. Dedicate time to: 1) Understanding biological processes step-by-step, 2) Practicing biological drawing and labeling, 3) Solving genetics problems, 4) Applying biological knowledge to real situations. For processes: create flowcharts, explain aloud, connect steps. For diagrams: practice regularly, follow conventions, time yourself. For genetics: work through problems systematically, use Punnett squares, show all working.

Disclaimer: This guide is for educational purposes only and is not an official NECTA publication. Always consult the latest NECTA syllabus, past papers, and official announcements for current examination requirements.

© 2023 Biology 1 Examination Guide | Designed for Form Six Biology Students

Examination Code: 051 | Paper: Biology 1 | Level: Advanced Certificate of Secondary Education (ACSEE)