JAMB - Physics (2013)

  • 1
    When a brick is taken from the earth's surface to the moon, its mass
    Відповідь
    (A)
    remains constant
  • 2
    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.
    Відповідь
    (C)
    43.3N
  • 3
    The pair of physical quantities that are scalar only are ?
    Відповідь
    (A)
    volume and area
  • 4
    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?
    Відповідь
    (C)
    2\(\sqrt{2}s\)
  • 5
    A train with an initial velocity of 20ms-1 is subjected to a uniform deceleration of 2m-2. The time required to bring the train to a complete halt is?
    Відповідь
    (B)
    10s
  • 6
    Calculate the apparent weight loss of a man weighing 70kg in an elevator moving downwards with an acceleration of 1.5ms-2.

    [g = 10ms-2]
    Відповідь
    (D)
    105N
  • 7
    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]
    Відповідь
    (C)
    0.2
  • 8
    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?
    Відповідь
    (C)
    1.3m
  • 9
    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
    Відповідь
    (C)
    3.3 x 103js-1
  • 10
    Calculate the work done when a force of 20N stretches a spring by 50mm.
    Відповідь
    (A)
    0.5J
  • 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
    Відповідь
    (C)
    3.6m3
  • 12
    Calculate the length which corresponds to a temperature of 20oC if the ice and steam points of an unguarded thermometer are 400 mm apart
    Відповідь
    (D)
    80mm
  • 13
    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
    Відповідь
    (D)
    99.92m
  • 14
    A gas at a pressure of 105Nm-2expands from 0.6m-3 to 1.2m3 at constant temperature, the work done is
    Відповідь
    (D)
    6.0 x 10 4J
  • 15
    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
    Відповідь
    (B)
    1:2
  • 16
    Steam from boiling water causes more damage on the skin than does boiling water because
    Відповідь
    (D)
    steam brings heat more easily by convection
  • 17
    What will happen to the boiling point of pure water when it is heated in a place 30m below sea level?
    Відповідь
    (A)
    It will be more than 100 oC
  • 18
    The rise or fall of a liquid in a narrow tube is because of the
    Відповідь
    (B)
    surface tension of the liquid
  • 19
    The mechanism of heat transfer from one point to another through the vibration of the molecules of the medium is
    Відповідь
    (B)
    conduction
  • 20
    A wave that travels through stretched strings is known as
    Відповідь
    (C)
    mechanical wave
  • 21
    A transverse wave and a longitudinal wave travelling in the same direction in a medium differ essentially in their
    Відповідь
    (C)
    direction of vibration of the particles of the medium
  • 22
    What is the velocity of sound at 100 oC if the velocity of sound at 0 oC is 340ms -1?
    Відповідь
    (C)
    397m-1
  • 23
    If a sonometer has a fundamental frequency of 450HZ, what is the frequency of the fifth overtone?
    Відповідь
    (A)
    2700Hz
  • 24
    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?
    Відповідь
    (A)
    0.05m
  • 25
    A ray of light passing through the centre of curvature of a concave mirror is reflected by the mirror at?
    Відповідь
    (A)
    0o
  • 26
    Total internal reflection will not occur when light travels from
    Відповідь
    (B)
    water into glass
  • 27
    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
    Відповідь
    (D)
    28
  • 28
    The angle of deviation of light of various colours passing through a triangular prism increases in the order
    Відповідь
    (A)
    red → green → blue
  • 29
    Calculate the force acting on an electron of charge 1.5 x 10-19C placed in an electric field of intensity 105Vm-1
    Відповідь
    (D)
    1.5x10-14N
  • 30
    Capacitors are used in the induction coil to
    Відповідь
    (C)
    prevent electric sparks
  • 31
    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
    Відповідь
    (A)
    4.0Ω
  • 32
    Which of the following obeys ohms laws?
    Відповідь
    (B)
    metals
  • 33
    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?
    Відповідь
    (C)
    N45
  • 34
    An electric device is rated 2000W, 250V. Calculate the maximum current it can take
    Відповідь
    (B)
    8A
  • 35
    When a charge moves through an electric circuit in the direction of an electric force, it
    Відповідь
    (C)
    loses potential energy and gains kinetic energy
  • 36
    To convert a galvanometer to a voltmeter, a
    Відповідь
    (A)
    high resistance is connected to it in series
  • 37
    Induced emfs are best explained using
    Відповідь
    (B)
    Faraday's law
  • 38
    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?
    Відповідь
    (C)
    4.6g
  • 39
    Calculate the energy of the third level of an atom if the ground state energy is - 24.8eV
    Відповідь
    (C)
    -2.75eV
  • 40
    In photo-emission, the number of photo-electrons ejected per second depends on the?
    Відповідь
    (D)
    intensity of the beam