1. The area under a force-tine graph represents A. change in kinetic energy. B. change in momentum, C. work done. D. change in internal energy.
2. From the principle of flotation, a body sinks in a fluid until it displaces a quantity of fluid equal to its own A. density. B. mass. C. weight. D. volume.
Suppose three identical steel balls Q.
R and S are placed on an undulating
ground as illustrated in the diagram
above. Which of the balls is/are in neutral equilibrium? A. S only. B. Q only C. R only. D. Q and S only
4. The length of a simple pendulum is
increased by a factor of four. By what
factor is its period increased? A. 0.5π
B. 2 C. 2π D. 4
5. The linear expansivity a, and cubic expansivity, y of a material are related by the equation A. y =a B. y =3a C. y = 2a D. y = ⅓a
6. Which of the illustrated graphs below represents a body moving with uniform retardation?
7. The correct relationship between the displacement, s, of a particle initially at rest in a linear motion and the time t, is A. s a t-² B. s a t-¹. C. s a t D. s a t²
8. The Joule is equivalent to A. kg m² s-¹ B. kg² m s-² C. kg m² s-² D. kg m s-¹
9. Which of the following statement(s)
is/are correct about a fixed mass of
gas compressed in an inexpansible
container? I. The average speed of
the molecules increases. II. The temperature of the gas increases. III. The molecules hit the walls of the container more often than before the compression. A. I only B. I and Il only C. I and III only D. I. II and III
10. An example of a mechanical wave is A. water, waves. B. radio waves.
C. X-rays. D. light rays.
11. Which of the following descriptions of the image formed by a plane mirror is not correct? The image is A. erect and
of the same size as the object. B. laterally inverted and of the same size as the object. C. erect and bigger than the object. D. virtual and of the same size as the object.
12. The efficiency of a wheel and axle is 100% and the ratio of their radii is 5:1. Calculate the effort required to lift a load of mass 20kg using this machine.[g= 10 ms-²] A. 20 NB. 25N C. 40N D. 100 N
13. A freely suspended compass needle on the earth’s surface settles in a plane called A. geographic meridian. B. magnetic meridian. C. magnetic declination. D. isoganals.
14. An object is placed at different distances, u, from a converging lens of
focal length, 15.0 cm. For what value
of u does the lens act as a simple microscope? A. u = 15 cm only. B. u = 30cm only C. u< 15 cm only D. u> 30
cm only.
15. The periodic rise and fall in the intensity of sound produced when two
notes of nearly equal frequencies are
sounded together is called A. doppler
effect. B. beat. C. interference. D. resonance.
16. The power of a lens is +2.5 D. What is its radius of curvature? A. 2.5 cm B. 25.0cm C. 40.0 cm D. 80.0 cm
17. The reason for having a large number of turns in the coil of a moving coil galvanometer is to A. make the deflection of the needle proportional to the current. B increase the sensitivity of the galvanometer. C. decrease the magnetic flux produced by the magnet. D. make the permanent magnet stronger.
18. Current is passed through two parallel conductors in the same direction. If the conductors are placed near each other, they will A. move in a circle. B. repel each other. C. remain stationary. D. attract each other.
19. The period of a 10 kHz radio wave travelling ‘at 3.0x 10^8 ms-¹ is A. 3.0x 10^5s. B. 1.0×10-⁴s C. 1.0x 10⁴ s. D. 3.0×10⁴s.
20. The magnetic material produced from the chemical combination of metal oxides and has a very high resistance to electric current is called a A. ferrite substance. B. paramagnetic substance. C. ferromagnetic substance. D. diamagnetic substance.
21. A body of mass, m, moving with velocity, v, has a wavelength associated with it. This phenomenon is called A. photoelectric effect. B. Heisenberg’s uncertainty principle. C. Compton effect. D. wave-particle paradox.
22. Which of the following statements
about a straight current-carrying wire
placed in a uniform magnetic field
is correct? The wire experiences A.
maximum motor force if the current
reverses its direction. B. no motor
force if it is parallel to the field. C. no
motor force if it is perpendicular to the field. D. a motor force with constant direction if either the current or the magnetic field is reversed
23. Three cells each of emf, 1.1 V, and internal resistance, 2 Ω, are connected in parallel across a 3 resistor. Determine the current in the resistor. A. 0.90 A. B. 0.39 A. C. 0.30 A. D. 0.01 A
24. Which of the following statements
about electric potential energy is not
correct? A. The electric potential energy of a positively charged particle
increases when it moves to a point of
higher potential. B. The electric potential energy of a negatively charged particle increases when it moves to a point of lower potential. C. The electric potential energy of a positively charged particle decreases when it moves to a point of higher potential. D. The work done in taking a charged particle around a closed path in an alectric feld is zero.
25. A galvanometer with a full scale deflection of 20 mA is converted to read 8 V by connecting a 395 Ω resistor in series with it. Determine the internal resistance of the galvanometer. A. 2.5Ω B. 5.0Ω C. 8.0Ω D. 10.0Ω
26. An inductor of inductance 10 His connected across an a.c. circuit source of 50 V, 100 Hz. What is the current in the circuit? [π =3.14] A. 0.200 A. B. 0.070A. C. 0.050 A. D. 0.008A
27. The speed of fast moving neutrons in a nuclear reactor can be reduced by
using A. graphite rods. B. concrete
shield. C. iron rods. D. boron rods.
28. In a series R-L-C circuit at resonance, impedance is A. maximum. B. minimum. C. capacitive. D. inductive.
29. A lamp is rated 240 V, 60 W. Determine the resistance of the lamp when lit. A. 120Ω B. 240Ω C. 540Ω D. 960Ω.
30. One major reason why electrical appliances in homes are normally earthed is that the A. person touching the appliance is safe from electric shock. B. appliances are maintained at a higher p.d. than the earth. C. appliances are maintained at a lower p.d than the earth, D. appliances are maintained at the same p.d with that of the earth.
31. In doping an intrinsic semiconductor to produce a p-type semiconductor, A. the semiconductor is heated up. B. a donor element is added. C. an acceptor element is added. D. the semiconductor is connected to a battery.
32. Arrange the following radiations in order of increasing ionization of air. I Alpha II. Gamma III. Beta A. I < III < II B. II <I <IlI C. Il<III < I D. I < II <lII
34. Gamma rays are produced When
high velocity electrons are abruptly A
stopped in metals. B. energy changed
occur within the nuclei of atoms. C.
energy changes occur within the electronic- structure of atoms. D. electrons are deflected in very strong magnetic fields.
35. The half-life of a radioactive substance is 15 hours. If at some instance, the sample has a mass of 512g, calculate the tine it will take ⅞ of the sample to decay. A. 15 hours B. 30 hours C. 45 hours D. 60 hours
36. When the direction of vibration of the particles of a medium is perpendicular to the direction of propagation of a wave, the wave is said to be A. longitudinal. B. transverse. C. mechanical. D. a sound wave.
37. A hunter fires a gun at a point 408m away from a clif. If he hears an echo 2.4 s later, determine the speed of the sound wave. A. 340 ms B. 380 ms C. 400 s D. 680 ms
38. The distance between the fixed points of a mercury-in-glass thermometer is 30 cm. Determine the temperature when the mercury level is 10.5 cm above the lower fixed point. A. 28.6 °CB. 30,0 °CC. 35,.0 °CD, 40.5 °C
39. Which of the following statements
about electromagnetic waves is not
correct? A. They carry energy as they travel through space. B. They travel
with the speed of light. C. They are
longitudinal. D The electric and magnetic fields are at right angles to each other.
41. Which of the following concepts is a method of heat transfer that does not require a material medium? A. Conduction B. Diffusion C. Convection D. Radiation.
42. Which of the following statements
about light travelling from one material medium to another is not correct? A. The refracted angie is less than the incident angle if the speed is higher in the first material. B. It bends away from the normal if the speed is lower in the first material. C. Its wavelength does not change. D. Its frequency
changes.
43. The engine of a car provides a forward force of 1240 N and the total resistive force on the car is 800 N. If the mass of the car is 1220 kg, determine the distance the car has to travel from the rest before acquiring a speed of 4 ms A. 44.0 m. B. 22.2 m C. 11.1 m D. 5.5 m
44. A quantity of water at 0 °C is heated to 30 °C. For each degree rise in temperature, its density will A. rise steadily. B. fall steadily C. fall and then rise. D rise and then falls.
45. A small object of mass 50g is released from a point A. Determine the velocity of the object when it reaches a point B, a vertical distance of 30m below A. [g=10ms-²]. A. 1.5ms-¹ B. 6.0 ms-¹ C. 17.3 ms-¹ D 2.5 ms-¹
46. Molecules move in radam motion
within a liquid. The total internal energy of the liquid depends on all of the following except its A.temperature. B. mass. C. specific het capacity. D. melting point.
47. The viscosity of a fluid depends on the following factors except the A. relative motion between the layers of the fluid. B. nature of the materials of the fluid. C. surface area of the fluid in contact. D. normal reaction in the fluid.
48. Using Vernier calipers, which of the following readings gives the correct measurement for the length of a rod? A. 4.1 cm B. 4.13 cm C. 4.125 cm D. 4.1254 Cm
49. The basic principle of operation of a beam balance is A. Archimedes principle. B. law of flotation. C. Hooke’s law. D. principle of moments.
50. In which of the following situations is friction not useful? A. Operation of a grinding machine B. Walking C. Application of brakes D. Moving piston in a sleeve
2022 WARC PHYSICS THEORY QUESTIONS
PART I
I. The diagram below illustrates the trajectory of a fired missile from point P at 250mns-¹
If the missile hits point Q after 40s.
Calculate the distance PQ.
2. State three properties of an intrinsic semiconductor.
3. The effective potential energy, E of a lunar satellite of mass, m, moving in
an elliptical orbit around the moon of is given by mass, distance of the satellite from the moon and G is the universal gravitational constant of dimensions, M-¹ L³ T-², Determine the dimensions of the angular momentum, K of the satellite using dimensional analysis.
4. A 50N force is applied to the free end of a spiral spring of force constant, 100 Nm-¹, Calculate the work done by the force to stretch the spring.
5(a) What is geostationary satellite?
(b) Name two types of LASERS.
6. State:
(a). the S.I. unit of the intensity of a black-body radiation.
(b) two features of the intensity-wave-length graph of a perfect blackbody at different temperature.
7. State three differences between magnetic and non-magnetic materials.
PART II
8ai). State the law ot inertia
i) List the law stated in 8a(i) to explain
how wearing a safety belt in a moving
vehicle could reduce the possibilities
of severe injuries when the vehicle is
involved in a collision.
b(i) Define the term moment of a force.
ii) A uniform plank measures 2m long
from its ends point A to point B, if
weight of the plank is 54N and it
rests on a knife edge 0.50m from end B and point A is supported by a vertical string so that AB balances horizontally:
i. Draw a force diagram for the arrangement;
ii. Determine the tension, T, in the
string
II. Determine the force, F, acting on the knife edge.
(c) State three difference between solid friction and viscosity.
(d) State one method of increasing the velocity ratio of a pulley system.
9a(i)State coulomb’s law of electrostatics.
(ii) The electron and proton of a hydrogen atom are separated by a mean distance
calculate R.
(ii) Define the volt.s
c) Explain why wOod is not suitable for use as the core of transformers.
(d) State one application of the cathode ray tube.
10a)State one condition each necessary for each of the following occurrences:
(i) constructive interference of waves;
(ii) total internal reflection;
(i) production of beats
(b) In a resonance tube experiment using a tuning fork of frequency 256Hz, the first position of resonance was 35cm, the next position was 100cm. Calculate the velocity of sound in air from the experiment.
c) State the three classificationg of musical instruments.
(i) Give one example each of the classifcations stated in 1Oc(i).
(d) Calculate the critical angle for light
travelling from glass to air. [refractive
index•of glass = 1.5]
(e) The speed of sound in a medium at a temperature of 102 °C is 240 ms-¹, If
the speed of sound in the medium is
310 ms-¹, Calculate its temperature.
11(a)State two factors that affect the rate of evaporation of a liquid.
(b) Explain the term latent heat.
(c) Explain each of the following phenomena:
i) One a dry day, water in a clay pot is
cooler than water in a rubber container.
ii) Cooking of food is faster in pressure
cooker than in an ordinary pot.
(d) A 40V electric heater is used to supply a current of 124 for 1400 seconds to a body of mass 1.5kg at its melting point. The body melts and its temperature rises by 60 °C in an extra 1.2 minutes.Calculate the:
i. latent heat of fusion of the body;
ii. specific heat capacity of the body.
e) State two differences between evaporation and boiling.
12. What is meant by the term artificial radioactivity?
ii. Complete the table below
b. (b) In an X-ray tube, an electron is accelerated from rest towards a metal
target by a 30 kV source. Calculate
(i) Plot a graph of kinetic energy, K.E.,
on the vertical axis and frequency, f,
on the horizontal axis starting both
axes from the origin (0,0).
ii) From the graph, determine the
I. Planck’s constant;
II. threshold frequency of radiations;
III. work function of the metal.
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