WAEC Physics 2000

1. When the surface of a piece of chalk is scrapped the tiny particles that flakes off are known as

• A. Matter

• B. Molecules

• C. Elements

• D. Atom

2. The diagram above represents a section of a pair of vernier calipers. The reading on the instrument is.

• A. 5.22cm

• B. 5.24cm

• C. 5.25cm

• D. 5.26cm

3. An iron rod is moved from the earth to the moon. Which of the following properties of the rod would remain unchanged? i. mass ii. weight iii. relative density

• A. i only

• B. ii only

• C. iii only

• D. i and iii only

4. A uniform cylindrical hydrometer of mass 20g and cross sectional area 0.54cm2 floats upright in a liquid. If 25cm of its length is submerged, calculate the relative density of the liquid. (Density of water = 1 gcm-3)

• A. 1.54

• B. 1.48

• C. 1.25

• D. 0.80

5. The apparent weight of a body wholly immersed in water is 32N and its weight in air is 96N. Calculate the volume of the body. (Density of water = 1000kgm-3, g = 10ms-3)

• A. 8.9 x 10m-3m3

• B. 6.4 x 10m-3m3

• C. 3.2 x 10m-3m3

• D. 3.0 x 10m-3m3

6. A wooden block of mass 1.6kg rest on a rough horizontal surface, if the limiting friction force between the block and the surface is 8N. Calculate the coefficient of friction. (g = 10ms-2)

• A. 0.6

• B. 0.5

• C. 0.3

• D. 0.2

7. A ball bearing is gently released from rest and allowed to fall through a viscous fluid. Which of the following statements about the motion is correct?

• A. its acceleration decreases before terminal velocity is attained

• B. when terminal velocity is attained the acceleration of the fluid becomes zero

• C. its velocity increases before terminal velocity is attained

• D. there is no resultant force on the ball before it attains terminal velocity

8. The driver of a car moving with uniform speed of 40ms-1observes a truck approaching from the opposite direction with a speed of 20ms-1. Calculate the speed of the car relative to that of the truck

• A. .5ms-1

• B. 2.0ms-1

• C. 20.0ms-1

• D. 60.0ms-1

9. A bus travelling at 15ms-1 accelerates uniformly at 4ms-2, what is the distance covered in 10s?

• A. 150m

• B. 170m

• C. 350m

• D. 600m

10. Which of the following sketches represents the velocity-time graph of the motion of a stone projected vertically upwards and allowed to return to the point of projection

v

1

11. The diagram above illustrates three forces T1, T2 and 100N in equilibrium. Determine the magnitude of T1

• A. 100 tan 30o

• B. \100cos/30o

• C. 200 sin 301

• D. 200/tan30o

12. A uniform metre rule of mass 90g is provided at the 40cm mark. If the rule is in equilibrium with an unknown mass m placed at the 10cm mark and a 72g mass at the 70cm mark, determine m

• A. 72g

• B. 102g

• C. 298g

• D. 504g

13. The resultant of two forces acting on an object is maximum when the angle between them is

• A. 180o

• B. 90o

• C. 45o

• D. 0o

14. The bob of a simple pendulum takes 0.25s to swing from its equilibrium position to one extreme end. Calculate its period

• A. 0.25s

• B. 0.50s

• C. 0.75s

• D. 1.00s

15. The period of oscillation pf a particle executing simple harmonic motion is 4ππ seconds. If the amplitude of oscillation is 3.0m. Calculate its period

• A. 1.5ms-1

• B. 3.0ms-1

• C. 4.5ms-1

• D. 6.0ms-1

16. An inelastic collision takes place between ball of known masses, just before the collision one of the ball is moving with a known velocity while the other is stationary. Which of the following physical quantities can be determined from the information given?

• A. speed of each of the ball after collision

• B. kinetic energy of each ball after collision

• C. total momentum of the ball after collision

• D. total momentum of the two ball after collision

• E. mutual forces excerted by the balls

17. Using the force displacement diagram shown above. Calculate the work done

• A. 2000J

• B. 1000J

• C. 20J

• D. 5J

18. A machine of efficiency 8% is used to raise a body of mass 75kg through a vertical height of 3m in 30s. Calculate the power input. (g = 10ms-2)

• A. 9.4W

• B. 60.0W

• C. 75.0W

• D. 93.8W

19. Two bodies P and Q, are in thermal equilibrium, which of the following statements about the bodies is correct?

• A. the temperature of Q is higher than that of P

• B. P and Q have the same heat capacty

• C. P and Q have the same mass

• D. P and Q are at the same temperature

20. The cubic expansivity of mercury is 1.8 x 10-4K-1 and the linear expansivity of glass 8.0 x 10-6K-1, calculate the apparent expansivity of mercury in a glass container

• A. 1.00 x 10-4K-1

• B. 1.56 x 10-4K-1

• C. 1.72 x 10-4K-1

• D. 2.04 x 10-4K-1

21. The diagram shows the variation of volume V of a glass with temperature at the point X is

• A. -32oC

• B. -100oC

• C. -273oC

• D. -373oC

22. The volume and pressure of a given mass of gas at 27oC are 76cm3 and 80cm of mercury respectively. Calculate the volume at s.t.p

• A. 36.2cm3

• B. 72.8cm3

• C. 100.0cm3

• D. 808.9cm3

23. A piece of metal of mass 50g is cooled from 80oC to 20oC. Calculate the amount of heat lost. (specific heat capacity of the material of metal = 450Jkg-1K-1)

• A. 4.50 x 103J

• B. 2.25 x 103J

• C. 1.80 x 103J

• D. 1.35 x 103J

24. The mass of water vapour in a given volume of air is 0.05g at 20oC, while the mass of water vapour required to saturate it at the same temperature is 0.15g. Calculate the relative humidity of the air

• A. 3.33%

• B. 5.55%

• C. 33.33%

• D. 55.55%

25. The temperature at which the saturated vapour pressure of a liquid is equal to the external atmospheric pressure is known as its

• A. dew point

• B. boiling point

• C. lower fixed point

• D. tripple point

26. A periodic pulse travels a distance of 20.0m in 1.00s. If its frequency is 2.0 x 103Hz. Calculate the wavelength.

• A. 1.0 x 10-3m

• B. 1.0 x 10-2m

• C. 2.0 x 10-2m

• D. 1.0 x 102m

27. A wave has an amplitude equal to 4.0m, angular speed 1/3π rads-1 and phase angle 2/3π rad. The displacement y of the wave particle is given as

• A. y = 4 sin π/3(t + 2)

• B. y = 4 sin π/3(t + 2π

• C. y = 4 sin π3(2t+1)

• D. y = 4 sin π/3 (t + 2)

28. In the diagram above, an incident ray AY makes an angle of 30o with the normal XY. If the mirror is rotated anticlockwise about Y through an angle of 20o, while AY is fixed, what angle will the reflected ray now make with the incident ray?

• A. 70o

• B. 80o

• C. 100o

• D. 120o

29. A concave mirror can be used to produce a parallel beam of light if a lighted bulb is placed

• A. between its focus and the pole

• B. at its focus

• C. at its centre of curveture

• D. between its focus and centre of curvature

30. A simple microscope forms an image 10cm from an eye close to the lens. If the object is 6cm from the eye, calculate the focal length of the lens

• A. 3.75cm

• B. 4.00cm

• C. 15.00cm

• D. 16.00cm

31. When white light passes through a triangular glass prism, there is dispersion because of

• A. diffraction of light

• B. polarisation of light

• C. the difference in speed of the components of light

• D. the interference of light waves in glass

32. In which of the following media does sound travel faster?

• A. water

• B. brass

• C. air

• D. wood

33. A turning fork of frequency 600Hz is sounded over a closed resonance tube. If the first and second resonant positions are 0.130m and 0.413m respectively, calculate the speed of sound in air

• A. 508.4ms-1

• B. 480.0ms-1

• C. 339.6ms-1

• D. 169.8ms-1

34. loudness increases as a vibrating tuning fork is brought nearer the end of a pipe containing air column due to

• A. resonance

• B. echo

• C. reverberation

• D. diffraction

35. the factor which enables the ear to distinguish between a note played on different instruments is the

• A. pitch

• B. speed

• C. harmonics

• D. loudness

36. An object is situated within the Earth’s gravitational field. Which of the following factor does not affect the acceleration of free fall g?

• A. the distance of the object from the centre of the earth

• B. the latitude of the earth on which the object is situated

• C. rotation of the earth

• D. the mass of the object

37. The capacitance of a parallel-plate capacitor is increased by making the area of the plates

• A. small and their seperation large

• B. large and their seperation small

• C. and their seperation small

• D. and their seperation equal

38. In the diagram above, the current passing through the 6ΩΩresistor is 1.5A. Calculate the current in the 30ΩΩ resistor

• A. 1.20A

• B. 0.90A

• C. 0.75A

• D. 0.60A

39. Calculate the terminal p.d. of the battery in the diagram

• A. 7.50V

• B. 9.00V

• C. 10.80V

• D. 1.25V

40. An immersion heater is rated 120W. How long does it take the heater to raise the temperature of 1.2kg of water by 15oC. (Assuming heat lost to the surrounding is negligible. Specific heat capacity of water = 4200 Jkg-1K-1C)

• A. 65.0 minutes

• B. 60.0 minutes

• C. 52.5 minutes

• D. 10.5 minutes

41. The region around a magnet in which the magnetic influence is experienced is called

• A. magnetic flux

• B. magnetic field

• C. magnetic meridian

• D. magnetic declination

42. If a bar magnet is accidentally broken into 3 pieces as shown in the diagram below, the polarities of P and Q respectively are

N S P+ +Q N S

• A. S and S

• B. N and S

• C. N and N

• D. S and N

43. A device used to prevent wearing away of the make and-brake contacts of an induction coil is called a\an

• A. fuse

• B. electroscope

• C. resistor

• D. capacitor

44. An inductor of inductance 10H carries a current of 0.2A. Calculate the energy stored in the inductor

• A. 0.1J

• B. 0.2J

• C. 1.0J

• D. 2.0J

45. calculate the inductance of an inductor whose reactance is one ohm at 50 Hz.

• A. 2.00 x 10-2H

• B. 6.36 x 10-2H

• C. 3.18 x 10-2H

• D. 4.55 x 10-2H

46. Borh’s theory provides evidence for the

• A. structure of the atom

• B. positive charge of an electron

• C. existence of energy level in the atom

• D. positive charge on a proton

47. A nuclide 20284Y emits in succession an α−particle and a β−particle. The atomic number of the resulting nuclide is

• A. 198

• B. 83

• C. 82

• D. 80

48. The half life of a radioactive substance is 14 days. If 48g of this substance is stored, after how many days will 1.5g of the original substance remain?

• A. 84 days

• B. 70 days

• C. 56 days

• D. 40 days

49. A material of mass 1.0 x 10-2kg undergoes a fission process which decreases its mass by 0.02 percent. Calculate the amount of energy released in the process. (c = 3.0 x 108ms-1)

• A. 1.8 x 1020J

• B. 1.8 x 1013J

• C. 1.8 x 1011J

• D. 1.8 x 1010J

50. Absorption line spectra exhibited by atoms is a result of

• A. change in the kinetic energy of a movimg atom

• B. instability of the nucleons

• C. excitation of an electron in the atom

• D. transition of an electron from a higher to a lower energy level