2013 JAMB Physics Past Questions

Questions

1. 1.

   A house has ten 40W and five 100W bulbs. How much will it cost the owner of the house to keep them lit for 10 hours if the cost of a unit is 5N?

   1. A.N90
   2. B.N50
   3. C.N45
   4. D.N5

   Show answer

   Answer: C. N45

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

2. 2.

   A ray of light passing through the centre of curvature of a concave mirror is reflected by the mirror at?

   1. A.0o
   2. B.45o
   3. C.90o
   4. D.180o

   Show answer

   Answer: A. 0o

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

3. 3.

   Calculate the energy of the third level of an atom if the ground state energy is - 24.8eV

   1. A.-9.20eV
   2. B.-8.20eV
   3. C.-2.75eV
   4. D.-1.75eV

   Show answer

   Answer: C. -2.75eV

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

4. 4.

   A cell of emf 1.5V is connected in series with a 1Ω resistor and a current of 0.3A flows through the resistor. Find the internal resistance of the cell

   1. A.4.0Ω
   2. B.3.0Ω
   3. C.1.5Ω
   4. D.1.0Ω

   Show answer

   Answer: A. 4.0Ω

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

5. 5.

   A simple pendulum of length 0.4m has a period of 2s. What is the period a similar pendulum of length 0.8m at the same place?

   1. A.8s
   2. B.4s
   3. C.2$\sqrt{2}s$
   4. D.$\sqrt{2}s$

   Show answer

   Answer: C. 2$\sqrt{2}s$

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

6. 6.

   If a pump is capable of lifting 5000kg of water through a vertical height of 60m in 15 min, the power of the pump is

   1. A.2.2.5 x 10 5js-1
   2. B.2.5 x 104js-1
   3. C.3.3 x 103js-1
   4. D.3.3 x 102js-1

   Show answer

   Answer: C. 3.3 x 103js-1

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

7. 7.

   The mechanism of heat transfer from one point to another through the vibration of the molecules of the medium is

   1. A.covection
   2. B.conduction
   3. C.radiation
   4. D.diffusion

   Show answer

   Answer: B. conduction

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

8. 8.

   The particle nature of light is demonstrated by the

   1. A.photoelectric effect
   2. B.speed of light
   3. C.colours of light
   4. D.diffraction of light

   Show answer

   Answer: A. photoelectric effect

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

9. 9.

   Calculate the work done when a force of 20N stretches a spring by 50mm.

   1. A.0.5J
   2. B.1.5J
   3. C.2.0J
   4. D.2.5J

   Show answer

   Answer: A. 0.5J

   Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

10. 10.

    The energy of a photo having a wavelength of 10-10m is (h= 6.63 x 10 -34Js, c =3.0 x 10 8$ms^{-1}$)

    1. A.2.0 x 10 -15J
    2. B.1.7 x 10 -13J
    3. C.2.0 x 10 -12J
    4. D.1.7 x 10 -12J

    Show answer

    Answer: A. 2.0 x 10 -15J

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

11. 11.

    What volume of alcohol will have same mass as 4.2m-3 of petrol? Density of alcohol = 8.4 x 10^2 kgm-3, density of petrol =7.2x10^2 kgm-3

    1. A.0.8m3
    2. B.1.4m3
    3. C.3.6m3
    4. D.49.m3

    Show answer

    Answer: C. 3.6m3

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

12. 12.

    A wave that travels through stretched strings is known as

    1. A.electromagnetic wave
    2. B.micro wave
    3. C.mechanical wave
    4. D.seismic wave

    Show answer

    Answer: C. mechanical wave

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

13. 13.

    In photo-emission, the number of photo-electrons ejected per second depends on the?

    1. A.frequency of the beam
    2. B.work function of the metal
    3. C.threshold frequency of the metal
    4. D.intensity of the beam

    Show answer

    Answer: D. intensity of the beam

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

14. 14.

    Calculate the length which corresponds to a temperature of 20oC if the ice and steam points of an unguarded thermometer are 400 mm apart

    1. A.20mm
    2. B.30mm
    3. C.60mm
    4. D.80mm

    Show answer

    Answer: D. 80mm

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

15. 15.

    The rise or fall of a liquid in a narrow tube is because of the

    1. A.viscosity of the liquid
    2. B.surface tension of the liquid
    3. C.friction between the walls of the tube and the liquid
    4. D.osmotic pressure of the liquid

    Show answer

    Answer: B. surface tension of the liquid

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

16. 16.

    When a brick is taken from the earth's surface to the moon, its mass

    1. A.remains constant
    2. B.reduces
    3. C.increases
    4. D.becomes zero

    Show answer

    Answer: A. remains constant

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

17. 17.

    Induced emfs are best explained using

    1. A.Ohm's law
    2. B.Faraday's law
    3. C.Colomb's law
    4. D.Lenz's law

    Show answer

    Answer: B. Faraday's law

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

18. 18.

    Calculate the force acting on an electron of charge 1.5 x 10-19C placed in an electric field of intensity 105Vm-1

    1. A.1.5x10-11N
    2. B.1.5x10-12N
    3. C.1.5x10-13N
    4. D.1.5x10-14N

    Show answer

    Answer: D. 1.5x10-14N

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

19. 19.

    The bond between silicon and germanium is

    1. A.dative
    2. B.covalent bond
    3. C.trivalent
    4. D.ionic

    Show answer

    Answer: B. covalent bond

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

20. 20.

    What is the velocity of sound at 100 oC if the velocity of sound at 0 oC is 340ms -1?

    1. A.497m-1
    2. B.440m-1
    3. C.397m-1
    4. D.240m-1

    Show answer

    Answer: C. 397m-1

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

21. 21.

    An object is moving with a velocity of 5m-1. At what height must a similar body be situated to have a potential energy equal in value with kinetic energy of the moving body?

    1. A.25.0m
    2. B.20.0m
    3. C.1.3m
    4. D.1.0m

    Show answer

    Answer: C. 1.3m

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

22. 22.

    Total internal reflection will not occur when light travels from

    1. A.water to air
    2. B.water into glass
    3. C.glass to air
    4. D.glass into water

    Show answer

    Answer: B. water into glass

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

23. 23.

    Steam from boiling water causes more damage on the skin than does boiling water because

    1. A.water has a high specific heat
    2. B.steam has latent heat of fusion
    3. C.the steam is at a highter temperature than the water
    4. D.steam brings heat more easily by convection

    Show answer

    Answer: C. the steam is at a highter temperature than the water

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

24. 24.

    A gas at a pressure of 105$Nm^{-2}$expands from 0.6m-3 to 1.2m3 at constant temperature, the work done is

    1. A.7.0 x 106J
    2. B.6.0 x 10 6J
    3. C.6.0 x 10 5J
    4. D.6.0 x 10 4J

    Show answer

    Answer: D. 6.0 x 10 4J

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

25. 25.

    What will happen to the boiling point of pure water when it is heated in a place 30m below sea level?

    1. A.It will be more than 100 oC
    2. B.It will be last than 100 oC
    3. C.It will still be at 100 oC
    4. D.It will be fluctuating

    Show answer

    Answer: A. It will be more than 100 oC

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

26. 26.

    A transverse wave and a longitudinal wave travelling in the same direction in a medium differ essentially in their

    1. A.frequency
    2. B.amplitude
    3. C.direction of vibration of the particles of the medium
    4. D.period of vibration of the particles of the medium

    Show answer

    Answer: C. direction of vibration of the particles of the medium

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

27. 27.

    A train with an initial velocity of 20$ms^{-1}$ is subjected to a uniform deceleration of 2m-2. The time required to bring the train to a complete halt is?

    1. A.5s
    2. B.10s
    3. C.20s
    4. D.40s

    Show answer

    Answer: B. 10s

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

28. 28.

    A piece of cork floats in a liquid. What fraction of its volume will be immersed in the liquid? [Density of the cork = 0.25 x 103kgm-3, Density of the liquid = 1.25 x 103kgm-3]

    1. A.0.8
    2. B.0.5
    3. C.0.2
    4. D.0.1

    Show answer

    Answer: C. 0.2

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

29. 29.

    If a current of 2.5A flows through an electrolyte for 3 hours and 1.8g of a substance is deposited, what is the mass of the substance that will be deposited if a current of 4A flows through it for 4.8 hours?

    1. A.2.4g
    2. B.3.2g
    3. C.4.6g
    4. D.4.8g

    Show answer

    Answer: C. 4.6g

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

30. 30.

    A man 1.5m tall is standing 3m in front of a pinhole camera whose distance between the hole and the screen is 0.1m. What is the height of the image of the man on the screen?

    1. A.0.05m
    2. B.0.15m
    3. C.0.30m
    4. D.1.00m

    Show answer

    Answer: A. 0.05m

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

31. 31.

    The angle of deviation of light of various colours passing through a triangular prism increases in the order

    1. A.red → green → blue
    2. B.green → violet → blue
    3. C.blue → red → green
    4. D.blue → green → red

    Show answer

    Answer: A. red → green → blue

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

32. 32.

    Calculate the apparent weight loss of a man weighing 70kg in an elevator moving downwards with an acceleration of 1.5$ms^{-2}$. [g = 10$ms^{-2}$]

    1. A.686N
    2. B.595N
    3. C.581N
    4. D.105N

    Show answer

    Answer: D. 105N

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

33. 33.

    Which of the following obeys ohms laws?

    1. A.electroytes
    2. B.metals
    3. C.diode
    4. D.glass

    Show answer

    Answer: B. metals

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

34. 34.

    If the linear magnification of the objective and eyepiece convex lenses of a compound microscope are 4 and 7 respectively. Calculate the angular magnification of the microscope

    1. A.2
    2. B.3
    3. C.11
    4. D.28

    Show answer

    Answer: D. 28

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

35. 35.

    The pair of physical quantities that are scalar only are ?

    1. A.volume and area
    2. B.moment and momentum
    3. C.length and displacement
    4. D.Impulse and time

    Show answer

    Answer: A. volume and area

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

36. 36.

    Capacitors are used in the induction coil to

    1. A.control circuits
    2. B.prevent distortion of electric fields
    3. C.prevent electric sparks
    4. D.dissipate energy

    Show answer

    Answer: C. prevent electric sparks

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

37. 37.

    When a charge moves through an electric circuit in the direction of an electric force, it

    1. A.gains both potential and kinetic energy
    2. B.gains potential energy and lose kinetic energy
    3. C.loses potential energy and gains kinetic energy
    4. D.loses both potential and kinetic energy

    Show answer

    Answer: C. loses potential energy and gains kinetic energy

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

38. 38.

    An electric device is rated 2000W, 250V. Calculate the maximum current it can take

    1. A.9A
    2. B.8A
    3. C.7A
    4. D.6A

    Show answer

    Answer: B. 8A

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

39. 39.

    The resultant of two forces is 50N. If the forces are perpendicular to each other and one of them makes an angle 0f 30o with the resultant, find its magnitude.

    1. A.100.0N
    2. B.57.7N
    3. C.43.3N
    4. D.25.0N

    Show answer

    Answer: C. 43.3N

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

40. 40.

    If a sonometer has a fundamental frequency of 450HZ, what is the frequency of the fifth overtone?

    1. A.2700Hz
    2. B.456Hz
    3. C.444Hz
    4. D.75Hz

    Show answer

    Answer: A. 2700Hz

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

41. 41.

    To convert a galvanometer to a voltmeter, a

    1. A.high resistance is connected to it in series
    2. B.high resistance is connected to it in parallel
    3. C.low resistance is connected to it in parallel
    4. D.low resistance is connected to it in series

    Show answer

    Answer: A. high resistance is connected to it in series

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

42. 42.

    Two liquids X and Y having the same mass are supplied with the same quantity of heat. If the temperature rise in X is twice that of Y, the ratio of specific heat capacity of X to that of Y is

    1. A.2:1
    2. B.1:2
    3. C.4:1
    4. D.1:4

    Show answer

    Answer: B. 1:2

    Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app

43. 43.

    A wire of length 100.0m at 30o has linear expansive of 2x10-5K-1 Calculate the length of the wire at a temperature of - 10oC

    1. A.100.08m
    2. B.100.04m
    3. C.99.96m
    4. D.99.92m

    Show answer

    Answer: D. 99.92m

    AI explanation

    Analysis

    To solve this problem, we need to calculate the change in length of the wire due to a change in temperature. This is a classic application of the Linear Expansivity formula.

    Concept

    The formula for linear expansion is:

    $L_2 = L_1(1 + \alpha\Delta\theta)$

    Where:

    • $L_1$ = Initial length = $100.0\text{ m}$
    • $L_2$ = Final length
    • $\alpha$ = Linear expansivity = $2 \times 10^{-5}\text{ K}^{-1}$
    • $\Delta\theta$ = Change in temperature = $(\theta_2 - \theta_1)$

    Step-by-Step Solution

    1. Identify the variables:

    • $L_1 = 100.0\text{ m}$
    • $\alpha = 2 \times 10^{-5}\text{ K}^{-1}$
    • $\theta_1 = 30^\circ\text{C}$
    • $\theta_2 = -10^\circ\text{C}$

    2. Calculate the change in temperature ($\Delta\theta$):

    $\Delta\theta = \theta_2 - \theta_1$

    $\Delta\theta = -10 - 30 = -40^\circ\text{C}$

    (Note: A change of $1^\circ\text{C}$ is equivalent to a change of $1\text{ K}$, so we can use $-40\text{ K}$ directly.)

    3. Apply the formula:

    $L_2 = 100[1 + (2 \times 10^{-5} \times -40)]$

    $L_2 = 100[1 + (-80 \times 10^{-5})]$

    $L_2 = 100[1 - 0.0008]$

    $L_2 = 100[0.9992]$

    $L_2 = 99.92\text{ m}$

    Conclusion

    The calculation shows that the wire contracts as the temperature drops from $30^\circ\text{C}$ to $-10^\circ\text{C}$. The final length is $99.92\text{ m}$.

    Exam Tip

    Always pay attention to the sign of your temperature change ($\Delta\theta$). If the final temperature is lower than the initial temperature, the change is negative, which means the material will contract (the length will decrease). If the temperature increases, the change is positive, and the material will expand.

    AI can make mistakes. Report anything that looks wrong.