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Section A: Compulsory Questions
For all multiple-choice questions, circle a letter
corresponding to the correct answer.
Identify the answer choice that best completes each of the
statements below.
a) ………………………………………………. is a contact force.
i)Friction force
ii) Nuclear force
iii) Gravitational force
iv) Magnetic force
Correct Answer
Friction force
b) Magnetic force is a force of attraction between a
…………………. and magnetic material.
i) copper wire
ii) magnet
iii) wooden table
iv) non-magnetic material
Correct answer
Magnet
C) ……………………………………...is a non-contact force.
i) Upthrust
ii) Friction force
iii) Air resistance
iv) Electric force
Correct answer
Electric force
D) A push or a pull in a given direction that can change the
motion of an object is called a(n)….
i) inertia
ii) velocity
iii) force
iv) accelerator
Correct answer
Force.
2) Complete each of the following statements using
appropriate term from the box.
|
Heat Solar energy Power Kinetic energy |
a) Kinetic energy of an object is the form of
energy that it possesses due to its motion.
b) Two forms of energy produced when wood burns are
light energy and Heat.
c) Power is defined as the rate at which work
is done.
d) Solar energy is radiation from the Sun that
is capable of generating electricity.
3) Draw an arrow from the item in column A that matches with
the item in column B
For example: f) → v)
|
Column A |
Column B |
|
a) Knife |
i) It is an
example of inclined plane |
|
b) Lever |
ii) It is a
type of simple machine that uses a wheel and rope to lift heavy loads. |
|
c) Pulley |
iii) It is an
example of wedge |
|
d) Ladder |
iv) It is a
bar that pivots around a fulcrum used for lifting or moving heavy things. |
a) ------------- > iii
b) --------------> iv
c) ---------------> ii
d) -------------- > i
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4) Identify the answer choice that best completes the
statement or answers the question.
a) Which of the following devices is based on the heating
effect of electric current?
i) Electric switch
ii) Electric cooker
iii) Electric battery
iv) Electric conductor
Correct answer
Electric cooker
b) What is an electric generator?
i) A device that generates electricity
ii) A path along which electricity can flow
iii) A device that stores electricity
iv) A device that measures electricity
Correct answer
A device that generates
electricity
c) If the symbols 𝐼𝐼, 𝑅𝑅
and 𝑉𝑉
represent electric current, electric resistance and voltage respectively, then
the formula of the electric power is:
i) RI
ii) R2 I
iii) V/I
iv) VI
Correct
VI
5) Choose the correct alternative from the given options.
a) Which of the following metals is the most common metal
used to make electrical wires?
i) Copper
ii) Zinc
iii) Lead
iv) Cobalt
Correct answer
Copper
b) What is the purpose of insulating electrical tools such
as screwdrivers?
i) To prevent user from getting electrocuted
ii) To reduce electricity consumption
iii) To make tools lighter for handling
iv) To improve the efficiency of tools
Correct
To prevent user from getting
electrocuted
c) Which of the following serves as protection against
overload or short-circuit in a house electrical circuit?
i) Resistor
ii) Switch
iii) Circuit breaker
iv) Electric lamps
Correct
Circuit breaker
d) What does the following symbol represent (figure
1)?
 |
| Figure 1 |
i) Direct current supply
ii) Electric Fuse
iii) Open electric switch
iv) Variable resistor
Correct
Direct current supply
6) The following figure 2
represents a voltage regulator circuit.
Complete the table below using
the names of the electronic components whose codes are shown in figure 2.
|
Code of the electronic component |
Name of the electronic component |
|
Q6 |
|
|
D5 |
|
|
D6 |
|
|
R9 |
|
Correct answer
D5: Zener Diode
D6: Diode
R9: Resistor
7) State whether each of the following statements is true or
false.
a) Hydraulic press works on Archimedes’ principle.……………….
False.
b) The buoyant force also known as the upthrust force is
given by the formula ρ × g × V, where 𝜌𝜌 is the density
of the liquid, 𝑉𝑉 is the volume of liquid displaced and
g is the acceleration due to gravity.…………………
True
c) A block of iron dropped in a vessel of water, sinks to
the bottom. This is because the weight of the water displaced by the block is
less than the weight of the block.………………
True
d) SI unit of atmospheric pressure is newton (N).…………………….
False
8) Select the correct alternative that answers the question
or completes the statement.
a) The pressure in a fluid at rest depends on….
i) surface area of the container
ii) volume of the liquid
iii) density of the liquid
iv) density of the container
Answer
Density of the liquid.
b) If the density of an object is less than the density of
water, what happens to the object when placed in water?
i) The object sinks completely
ii) The object becomes denser
iii) The object becomes heavier
iv) The object floats
Answer
The object floats
c) The three containers in figure 3 are filled with water to
the same level. Rank the hydrostatic pressures at the bottom of the containers.
i) 𝑃𝑃1>𝑃𝑃2>𝑃𝑃3
ii) 𝑃𝑃1=4𝑃𝑃2>𝑃𝑃3
iii) 𝑃𝑃1<𝑃𝑃2
iv) 𝑃𝑃1=𝑃𝑃2=𝑃𝑃3
Answer
P1 = P2 = P3.
d) The pressure exerted by a person on the Earth’s surface
is minimum when he/she…
i) stands on his/her feet.
ii) sleeps on the ground.
iii) sits with folded legs.
iv) stands on one foot.
Answer
Sleeps on the ground
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9) Identify the answer choice that best completes the
statement or answers the question.
a) a) The speed of a body undertaking linear motion
is given by 𝑣𝑣=𝑎𝑎𝑎𝑎
where t is time and 𝑣𝑣 is speed of the body, then the
dimensional formula of acceleration 𝒂 is :
i) [𝐿𝐿𝑇𝑇−1]
ii) [𝐿𝐿𝑇𝑇−2]
iii) [𝑀𝑀𝑇𝑇−1]
iv) [𝑀𝑀𝐿𝐿−2]
Correct
[ LT-2]
b) In an experiment, it is found that the
experimental value is very close to the true value, hence the experimental
value can be called…………….
i) accurate
ii) sensitive
iii) suitable
iv) precise
Answer
Accurate
c) How many significant figures are in the number 406.060?
i) 3
ii) 4
iii) 5
iv) 6
Answer
6
10) Select the correct alternative that answers the question
or completes the statement.
a) In the expression 𝜀𝜀=−∆∅
∆𝑡𝑡 the negative
sign signifies that
i) the induced emf is produced only when magnetic flux
decreases.
ii) the induced emf opposes the change in the magnetic flux.
iii) the induced emf is opposite to the direction of the
flux.
iv) the induced emf is independent of change in magnetic
flux.
Answer
The induced emf opposes the
change in the magnetic flux
b) If we increase the number of turns in a coil subjected to
a varying magnetic flux, what happens to the induced electromotive force (emf)?
i) Induced emf increases
ii) Induced emf decreases
iii) Induced emf remains the same
iv) Induced emf decreases then increases
Correct
Induced emf increases
c) What happens to the electric current induced in a coil
while accelerating a magnet inside it?
i) reverses
ii) decreases
iii) remains constant
iv) increases
Answer
Increases
11) a) Figure 4 shows a transformer whose coils of wire are
wound around an iron core.
a) Use the step up transformer or step down transformer to name the type of the above transformer.
This is a step-down
transformer, as the secondary coil has fewer turns than the primary coil.
b) Why does a real transformer have an efficiency that is
less than 100%?
i) Because some energy is lost as heat in the coils and
core.
ii) Because transformer only works with direct current.
iii) Because transformer only works at very high voltages.
iv) Because a transformer cannot be used for transmitting
electricity over long distances.
Answer
Because some energy is lost
as heat in the coils and core.
c) A step-up transformer is used before electricity
is transmitted by overhead cables. Which statement explains why the step-up
transformer is used?
i) It increases the electric current to increase the speed
at which the electricity travels.
ii) It increases the electric current to reduce energy loss
in the cables.
iii)It increases the voltage to increase the speed at which
the electricity travels.
iv) It increases the voltage to reduce energy loss in the
cables.
Answer
It increases the voltage to
reduce energy loss in the cables.
12) Consider the speed-time graph of a body shown in figure
5 and select the correct option that answers the question.
a) The acceleration of the body from O to A is equal to
i) 4 m/s2
ii) 24 m/s2
iii) 6 m/s2
iv) 1.5 m/s2
Correct
1.5 m/s².
b) The distance travelled by the body from A to B is
i) 0 m
ii) 36 m
iii) 40 m
iv) 60 m
Correct
36 m.
13) An object of mass 10 kg is moving with a velocity of 4
m/s. Its velocity increases from 4 m/s to 8 m/s when a force acts on it for 0.2
s.
a) What is the linear momentum P1 of the object before the
force acts?
i) 20 kgm/s
ii) 40 kgm/s
iii) 80 kgm/s
iv) 160 kgm/s
Correct
40 kgm/s.
b) What is the linear momentum P2 of the object after
the force acts?
i) 20 kgm/s
ii) 40 kgm/s
iii) 80 kgm/s
iv)160 kgm/s
Correct
80 kgm/s.
c) Find the change in linear momentum ∆𝑃𝑃=𝑃𝑃2−𝑃𝑃1
produced by the applied force
i) 0 kgm/s
ii) 20 kgm/s
iii) 40 kgm/s
iv) 80 kgm/s
Correct
40 kgm/s
d) What is the value of the impulse acting on the
object due to the applied force?
i) 0 Ns
ii) 20 Ns
iii) 40 Ns
iv) 80 Ns
Answer
40 Ns.
14) What will happen to the total mechanical energy of a
falling system if air resistance and friction force are present? Explain your
answer.
Mechanical Energy The total mechanical energy will decrease.
Because of air resistance and friction, work is done against these
non-conservative forces, causing some mechanical energy to be dissipated as
heat (thermal energy) to the surroundings.
15) Discuss briefly any two environmental factors that
affect plant growth. Use less than 10 lines to develop your ideas.
Plant Growth Factors Two environmental factors that affect plant growth are sunlight and water. Sunlight is required as the primary energy source for photosynthesis, allowing the plant to produce food. Water is essential for transporting dissolved nutrients from the soil through the plant's root system and maintaining cell structure.
Also read Mathematics Chemistry National Examination here
Section B: Attempt any three
questions
16) Thermodynamics in Physics is a branch that deals with
heat, work and temperature, and their relation to energy, entropy, radiation
and physical properties of matter.
a) Complete the following statements using the terms from
the list of states of matter: gas, liquid and solid.
i) Solid has
definite shape and definite volume.
ii) Liquid has definite volume and it takes the
shape of the container.
iii) Gas does not
have definite shape and volume.
b) State whether each of the following statements is true or
false.
i) The second
law of Thermodynamics states that the heat energy cannot spontaneously flow
from a body at a lower temperature to a body at a higher temperature without
the addition of energy True
ii) If you mix equal masses of two substances at
different temperatures, the final temperature will be the average of the two
initial temperature False (This
depends on their specific heat capacities)
iii) During the entire melting process of solid, the
temperature changes. False
c) In a certain process 523 J of heat is added to a system.
The system does work equivalent to 781 J on the surrounding atmosphere.
i) What is the change in internal energy for the system?
Using the First Law of Thermodynamics: Delta U = Q - W. Heat
added (Q) = 523 J. Work done by the system (W) = 781 J. U = 523 - 781 = -258 J.
c) Does the internal energy of the gas decrease or increase?
Explain your answer.
The internal energy decreases because $\Delta U$ is
negative. The system expended more energy doing work on the surroundings than
it absorbed as heat.
17) An object 3 cm high is placed 15 cm from a concave
mirror of focal length 6 cm as shown below, not to scale, in the figure 6.
a) Angle of incidence of a ray of light on a concave
mirror is equal to the angle of reflection. True or false?
True.
b) Complete the following statements with suitable terms or
value from the box:
|
6 centre of
curvature focal point parallel
Perpendicular 12 |
Two terms and one number are distractors.
i) The radius of curvature of the above concave
mirror r =………… cm.
r = 12 cm (r = 2f).
ii) A ray of light that passes through the focal
point of a concave mirror will reflect…………………….to the principal axis.
Reflect parallel.
iii) A ray of light passing through the ………………………. of
a concave mirror is reflected back along the same path.
centre of curvature.
c) Find the position 𝑣𝑣 of the image formed by the above concave mirror.
d) Determine the size ℎ′ of the
image.
e) Is the image real or virtual and upright or
inverted?
i) Virtual and inverted
ii) Virtual and upright
iii) Real and upright
iv) Real and inverted
Answer
iv) Real and inverted
18) A 3.0 Ω resistor, an unknown resistor, R, and two
ammeters, A1 and A2 are connected with a 12-volt source as shown in figure 7.
Ammeter A2 reads an electric current of 5.0 amperes. 3.0 Ω resistor and 𝑅𝑅
are connected in parallel.
a) i) Are the electrical appliances at home connected in
series or in parallel?
Parallel.
ii) What is the potential difference/voltage between the
terminals 𝑎𝑎 and 𝑏𝑏 of the 3.0 Ω
resistor?
12 V (Components in parallel share the source voltage).
ii) What is the instrument used for measuring
electric potential difference?
Voltmeter.
b) Calculate:
i) the electric current measured by ammeter A1.
ii. the electric current passing through the resistor R.
iii. the resistance of the unknown resistor, R.
iv) The equivalent resistance of the electric
circuit.
19) a) Complete the following statements using suitable
terms and symbols:
i) When the temperature of a rod of copper increases,
its length ………………. due to linear expansion.
Increases.
ii) If the symbol of the coefficient of linear expansion is 𝛼𝛼 and the symbol of the coefficient of volumetric/cubic expansion is 𝛾𝛾 then the relation between the two coefficients is ……………. = 3 ………….
iii) Which mode of heat transfer works best with
solids? Justify your answer.
Conduction works best with solids because their atoms
are tightly packed together, allowing vibrations and free electrons to easily
pass kinetic energy to neighboring atoms.
b) calorimeter of mass 0.050 kg and specific heat capacity
420J/kg° C contains 0.0507 kg of water at 20 °C in thermal equilibrium with the
calorimeter. A metal piece of mass 0.020 kg at 100° C is dropped into the
calorimeter. After stirring, the final temperature of the mixture is found to
be 22°C. The specific heat capacity of water is 4200 J/kg°𝐶𝐶.
Assume that in this experiment no heat is lost to the surroundings.
Calculate:
i) Heat energy
gained by water. Its temperature increased from 20°C to 22°C.
ii) Heat energy gained by the calorimeter. Its temperature
increased from 20°C to 22°C.
iii) Heat energy lost by the metal piece of unknown specific
heat capacity Its temperature decreased from 100°C to 22°C.
iv) The specific heat capacity of the metal piece.
20) a) i) Sketch electrostatic field lines around a positive electric point charge Q.
ii) ii) Complete this statement by using two terms
“repel” and “attract” Unlike electric charges attract each other while like
electric charges repel each other.
b) When a charged rod is held close to a metal sphere placed
on an isolated stand, the charge distribution on the sphere is shown in figure
8.
i) Is the sign of electric charge on the rod positive or negative?
Negative. The rod pushes negative charges to the far side of the sphere and attracts positive charges to the near side
ii) What are two methods of charging body?
Friction and Induction (or Conduction).
c) Two opposite electric point charges A and B of -3×10−9𝐶𝐶
and +3×10−9𝐶𝐶 respectively are situated 0.20 m
apart in air. Position Y is 0.10 m beyond the second electric charge, as shown
in figure 9 where the prefix 𝑛𝑛=10−9.
i) Copy the diagram and apply Coulomb’s law to draw the
electrostatic force 𝐹𝐹2 ⃗⃗⃗ exerted by A on B.
i & ii) Force vectors F1 and F2 should be drawn pointing
toward each other along the dotted line between A and B, representing an
attractive force.
Section C: Compulsory question (15 marks)
𝑙=……………………………………………cm.
w=…………………………………………. cm.
h=……………………………………………cm.
b) Why is the value of 𝑉𝐴𝐴 being only an approximation of the volume of the modelling block.
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