JAMB - Physics (2025)

  • 1
    Which of these colours in the visible spectrum has the longest wavelength?
    Απάντηση
    (A)
    Red
  • 2
    The power of a lens in diopters is
    Απάντηση
    (B)
    \(\frac{1}{\text{f}}\)
  • 3
    A man moves 6.0m East and then 10.0m N30ºE. How far is he from his starting point?
    Απάντηση
    (C)
    14.0m
  • 4
    The density of water is 1g/cm\(^3\) while that of ice is 0.9g/cm\(^3\). Calculate the change in volume when 90g of ice is completely melted.
    Απάντηση
    (D)
    10cm\(^3\)
  • 5
    The graphical representation of the pressure law is always a straight line passing through the origin, only if the temperature scale is
    Απάντηση
    (D)
    thermodynamic
  • 6
    According to the kinetic theory of gases, the pressure exerted by a gas on the walls equals.
    Απάντηση
    (D)
    Rate of change of momentum imparted to the walls per second per unit area.
  • 7
    Which of the following is not true about a wave in a plucked string?
    Απάντηση
    (D)
    It is longitudinal
  • 8
    The emf of a cell is the potential difference across its terminals when it is in
    Απάντηση
    (C)
    open circuit
  • 9
    The thermometric property of mercury is best on the change in
    Απάντηση
    (B)
    volume with temperature
  • 10
    Some of the features of the human eye that greatly help to refract light entering the eyes are
    Απάντηση
    (A)
    cornea and lens
  • 11
    When both the object and its image move together in the same direction relative to the observer, then there is
    Απάντηση
    (A)
    no parallax error
  • 12

    The diagram above shows a magnetic field due to a

    Απάντηση
    (C)
    current-carrying straight conductor
  • 13
    I. The colour of light depends on its frequency II. When white light is dispersed by a triangular prism, yellow is deviated more than green III. Rainbows are formed when rains fall heavily. Which of the above statements is/are correct about dispersion and colours?
    Απάντηση
    (B)
    I only
  • 14
    A Force 18 N pulls a 40 kg mass on a horizontal floor at 0.3 ms\(^{-2}\). Find the coefficient of friction.
    Απάντηση
    (B)
    0.015
  • 15
    A 500W electric oven plugged into a 220 V source will consume an electric current of
    Απάντηση
    (B)
    2.27A
  • 16
    A hydraulic press consists of two cylinders of cross-sectional radius r\(_1\) and r\(_2\). If a force of 200N applied to the smaller piston (r\(_1\)), causes a force of 3200N to be transmitted onto the larger piston (r\(_2\)). The ratio r\(_1\): r\(_2\) is?
    Απάντηση
    (A)
    1:4
  • 17
    The gravitational pull between two bodies is 20N. Find the gravitational pull when their distance of separation is doubled.
    Απάντηση
    (B)
    5N
  • 18
    The volume of a 1 cm\(^3\) metal ball increases by 0.0018 cm\(^3\) when heated through temperature θ. If the linear expansivity of the ball is 2.0 x 10\(^{-5} K^{-1}\), find θ.
    Απάντηση
    (C)
    30°C
  • 19
    For a gas, which pair of variables is inversely proportional to each other (provided other conditions are constant), where P = pressure, T= temperature, V= volume, and n= number of molecules?
    Απάντηση
    (B)
    P, V
  • 20
    A boy uses a single string pulley system to lift a mass of 20kg moving with a velocity of 5ms\(^{-1}\). What is the power developed by the boy if g = 10ms\(^{-2}\)?
    Απάντηση
    (B)
    1000W
  • 21
    Without considering the containing vessel, what mass of boiled water can raise the temperature of 8 kg of water from 25°C to 60°C when mixed in a heat-proof container?
    Απάντηση
    (B)
    7kg
  • 22
    Which of the following has the least thermal conductivity?
    Απάντηση
    (A)
    air
  • 23
    5400kJ of heat energy was lost when some amount of steam condensed to water for drinking purposes at 15º C. What is the quantity of water collected? [L\(_f \) = 2.26 × 10\(^6\) Jkg\(^{-1}\), c\(_w\) = 4200 Jkg\(^{-1}K^{-1}\)]
    Απάντηση
    (D)
    2.06 kg
  • 24
    Charge carriers in doped semiconductors are
    Απάντηση
    (D)
    electrons and holes
  • 25
    If the critical angle for a glass–air boundary is 45º, what is the refractive index of the glass?
    Απάντηση
    (A)
    \(\sqrt{2}\)
  • 26
    The volume of a fixed mass of gas at 0º C is 200 m\(^3\). What is its volume at 273º C at constant pressure?
    Απάντηση
    (B)
    400 m\(^3\)
  • 27
    The device that operates using the magnetic effect of electric current is
    Απάντηση
    (C)
    Electric bell
  • 28
    Calculate the decay constant of a radioactive isotope of half-life 138.5 s.
    Απάντηση
    (A)
    5.0 × 10\(^{-3}\) s\(^{-1}\)
  • 29
    How long will it take to heat 4 kg of water from 30ºC to 65ºC using an electric kettle taking 5 A from a 240 V supply?
    (Specific heat capacity of water = 4200 J kg\(^{-1}\) K\(^{-1}\))
    Απάντηση
    (C)
    490 s
  • 30

    The figure shows a uniform metre rule of weight 100 N balanced by a knife edge at the 10 cm mark and a cord attached at the 85 cm mark. What is the tension in the string?

    Απάντηση
    (B)
    53.33 N
  • 31
    What form of energy is present in the food we eat?
    Απάντηση
    (D)
    Chemical
  • 32
    What magnitude of electric current can store 2.5 J of energy in a 3 H induction coil?
    Απάντηση
    (A)
    1.29 A
  • 33
    A machine has an efficiency of 80%. If the input work is 200J, the output work is?
    Απάντηση
    (B)
    160J
  • 34
    A wooden block of relative density 0.4 floats in a liquid of density 1600 kg m\(^{-3}\). What fraction of its volume is immersed?
    Απάντηση
    (C)
    0.25
  • 35
    Lining the walls of an auditorium with perforated materials reduces
    Απάντηση
    (A)
    reverberation
  • 36
    If an object sinks in water, it means that
    Απάντηση
    (A)
    Its density is greater than that of water
  • 37
    A well-lagged thin metal rod of length 0.2 m has a temperature gradient of 416 K m\(^{-1}\). If one end is at 233º C, what is the temperature at the other end?
    Απάντηση
    (D)
    316.28°C
  • 38
    The movement of particles in liquids and gases is referred to as
    Απάντηση
    (C)
    Brownian motion
  • 39
    What mass of silver is deposited during electrolysis when a current of 0.8 A flows for 25 minutes?
    Απάντηση
    (D)
    1.34g
  • 40
    The thermal capacity of a body depends on one of the following
    Απάντηση
    (C)
    Nature and mass
  • 41
    What is the pressure exerted by 4.5m\(^3\) of gas at 17ºC in a cylinder if the number of moles is 8.3 moles? (R = 8.31 JK\(^{-1}\)mol\(^{-1}\))
    Απάντηση
    (D)
    4445Pa
  • 42
    The tangential force acting on an object that opposes it from sliding freely on the adjacent surface is called
    Απάντηση
    (C)
    Frictional force
  • 43
    The point where no magnetic effect is felt around a magnet is
    Απάντηση
    (D)
    Neutral point
  • 44
    If the specific gravity of a liquid is 0.76, calculate its density((\(\rho_w\) = 1000Kgm\(^{-3}\))
    Απάντηση
    (A)
    760Kgm\(^{-3}\)
  • 45
    Copper of 0.2g and silver of 1.2g are deposited when current is passed through copper and silver voltameter. Calculate the electrochemical equivalent, Z of silver if that of copper is 0.00028gC\(^{-1}\)
    Απάντηση
    (A)
    1.68 x 10\(^{-3}\)gC\(^{-1}\)
  • 46
    Calculate the heat capacity of a material that absorbs 48KJ of heat at a differential temperature of 53ºC
    Απάντηση
    (C)
    905.7JK\(^{-1}\)
  • 47
    Which of the following electromagnetic spectra has the shortest wavelength?
    Απάντηση
    (B)
    X - rays
  • 48
    A wire of radius 0.3cm is used to lift a block of 1.5kg. Calculate the stress introduced into the wire [ take g = 10m/s\(^2\)]
    Απάντηση
    (C)
    53 x 10\(^4\)Nm\(^{-2}\)
  • 49
    The quantity of heat required to convert 5kg of ice at its melting point to water without a change of temperature is
    Απάντηση
    (D)
    Latent heat of fusion.
  • 50
    Which of the following is better for measuring a very small resistance?
    Απάντηση
    (B)
    Wheatstone bridge
  • 51
    In an A.C circuit, the instantaneous current is 7A. What is the root mean square(r.m.s) value of the current I\(_{r.m.s}\)
    Απάντηση
    (A)
    5A
  • 52
    Calculate the depth of a swimming pool if the apparent depth is 10cm(refractive index of water is 1.33)
    Απάντηση
    (C)
    13.3cm
  • 53
    A 5 \(\mu\) positively charged particle is moving at 45º to the direction of magnetic field with 3 x 10\(^4\)m/s speed. If it experiences a force of 6N, what is the value of the flux density of the field?
    Απάντηση
    (D)
    56.57T
  • 54
    The dimensional symbol of tension in a string is expressed as
    Απάντηση
    (D)
    M L T\(^{-2}\)
  • 55

    From the above circuit, calculate the impedance ((\(\pi\) = \(\frac{22}{7}\), f = 50Hz)

    Απάντηση
    (B)
    163.5\(\Omega\)
  • 56
    What pressure would a 5000N weight of water exert at the bottom of a reservoir containing it if its length and breadth are 10m and 5m, respectively
    Απάντηση
    (C)
    100Pa
  • 57
    Standing waves are produced by
    Απάντηση
    (D)
    waves that reflect off a boundary and interfere with themselves
  • 58

    From the above figure, a uniform meter rule is suspended by two cords from a height. Calculate T?

    Απάντηση
    (C)
    19.24N
  • 59

    From the diagram above, the sine of the angle of refraction in glass is

    Απάντηση
    (B)
    0.3
  • 60
    What happens to the speed of sound in air when the pressure increases at a constant temperature
    Απάντηση
    (A)
    Unchanged
  • 61
    The operation of a photovoltaic cell is possible by the action of
    Απάντηση
    (A)
    Semi-conductor
  • 62
    A concave mirror of focal length 20cm produces an erect image that is four times the object, the object distance from the mirror is
    Απάντηση
    (A)
    less than 20cm
  • 63

    The resultant of the force shown above is

    Απάντηση
    (B)
    5.00N
  • 64
    A circular parallel plate capacitor with radius 6cm is separated by 0.12cm. Calculate the capacitance of the capacitor [\(\pi\) = 3.142, ε\(_0\) = 8.85 x 10\(^{-12}\)Nm\(^2\)C\(^2\)]
    Απάντηση
    (C)
    8.3 x 10\(^{-11}\)F
  • 65
    Calculate the specific heat capacity of a metal rod of mass 0.025kg whose temperature was raised by 15ºC when 1000J of heat energy was added to the rod(assuming the heat loss to the surrounding is negligible)
    Απάντηση
    (D)
    2666.7JKg\(^{-1}\)K\(^{-1}\)
  • 66
    The speed of sound in air is 60 m/s. How far from the centre of a storm is an observer who hears a thunder clap 4s after the flash of the lightning?
    Απάντηση
    (D)
    240m
  • 67
    Which of the following thermometer types best responds to a change in temperature
    Απάντηση
    (B)
    Resistance thermometer
  • 68
    A 25cm long pinhole camera produces a one-fifth of an object's size. Calculate the object distance
    Απάντηση
    (D)
    1.25m
  • 69
    What is the mass of a particle with speed 2.7 x 10\(^8\)m/s and wavelength 4.0 x 10\(^{-7}\)mm? (h = 6.63 x 10\(^{-34}\)Js)
    Απάντηση
    (B)
    6.1 x x 10\(^{-31}\)Kg
  • 70
    At what distance from a 1.2 x 10\(^{-7}\)C point charge will the electric field intensity be equal to 4.8 x 10\(^{-4}\)NC\(^{-1}\) [ Take \(\frac{1}{4\pi ε_0}\) = 9.0 x 10\(^9\)]
    Απάντηση
    (B)
    3.0Km
  • 71

    Using the oscillating simple pendulum above, the maximum kinetic energy is obtained at

    Απάντηση
    (A)
    Q
  • 72
    A collection of condensed suspended dust particles in the air constitute
    Απάντηση
    (B)
    fog
  • 73
    A body is moving initially at 4m/s. If it's impulse after accelerating at 5m/s\(^2\) for 2s is 60Kgms\(^{-1}\). What is its mass?
    Απάντηση
    (C)
    6Kg
  • 74
    A bore made in an aluminium block at 34ºC is 3.48cm\(^3\). What is the new bore when the temperature was raised to 340ºC [α\(_a\) = 24 x 10\(^{-6}\)K\(^{-1}\)]
    Απάντηση
    (B)
    3.83cm\(^3\)
  • 75
    A short-sighted person's far point is 95cm. The defect can be corrected using
    Απάντηση
    (C)
    Diverging lens of focal length 95cm
  • 76
    A refrigerator uses 150W. If it is kept on for 336 hours nonstop. What is the energy consumed in Kwh?
    Απάντηση
    (C)
    50.40Kwh
  • 77
    The commonly used materials for shielding or screening magnetism is
    Απάντηση
    (C)
    Soft iron
  • 78
    One of the following is not a radiation detector
    Απάντηση
    (A)
    Electrophorus
  • 79
    What is the electrolyte used in wet Leclanche cell
    Απάντηση
    (C)
    Ammonium chloride
  • 80
    In electromagnetic induction, the generated electricity is actually a voltage called
    Απάντηση
    (A)
    Induced emf
  • 81
    Which of the following is a basic Unit?
    Απάντηση
    (D)
    Ampere
  • 82

    The acceleration of the body given above ( upthrust = 10N)

    Απάντηση
    (C)
    7.5m/s\(^2\)
  • 83
    The distance between two successive trough points of a wave is
    Απάντηση
    (B)
    a wavelength
  • 84
    What colour has the lowest frequency in the spectrum of white light?
    Απάντηση
    (A)
    Red
  • 85
    If 10 objects, tinsels are placed between the mirror of a Kaleidoscope with an inclination of 30º, how many images are formed?
    Απάντηση
    (A)
    110
  • 86
    When capacitors are connected in series across a potential difference, there is a loss in their stored energy because:
    Απάντηση
    (D)
    decrease in the overall capacitance of the capacitors
  • 87

    The diagram above is a vector field. Determine the magnitude of the vector

    Απάντηση
    (C)
    2\(\sqrt{2}\)NC\(^{-1}\)
  • 88
    The focal length of the natural eye lens is variable due to the action of the
    Απάντηση
    (B)
    Ciliary muscle
  • 89
    An annular eclipse is formed when
    Απάντηση
    (A)
    The sun, moon, and earth comes in straight line
  • 90

    If a positively charged rod is brought close to the cap in the diagram above, the divergence

    Απάντηση
    (B)
    Increases
  • 91
    If the weight of an object on the Earth's surface is 2.5 x 10\(^3\)N, what is its weight on the moon's surface if the gravitational force of the moon is one-sixth of the Earth's(g = 10m/s\(^{-2}\))
    Απάντηση
    (B)
    416.67N
  • 92
    A boat or airplane has a pointed front or head. This is to
    Απάντηση
    (A)
    Reduce the friction of fluid
  • 93
    A gas is cooled at a constant pressure from 57ºC was observed to shrink one-fifth (1\5) of its original volume of 2.00cm\(^3\). Find its new temperature
    Απάντηση
    (B)
    -207\(^0\)C
  • 94
    The gravitational force between two masses, P and Q, is 10N, find the new value of the force if both masses are doubled
    Απάντηση
    (A)
    40.0N
  • 95
    If the length of a simple pendulum is 120cm, calculate its frequency [\(\pi\) = \(\frac{22}{7}\) g = 10ms\(^{-2}\)]
    Απάντηση
    (D)
    0.5Hz
  • 96

    From the above graph, what is the distance covered in the last stage of the motion?

    Απάντηση
    (B)
    28m
  • 97

    Assuming E\(_1\), E\(_2\), and E\(_3\), are equal, then the total e.m.f of the arrangement will be given by

    Απάντηση
    (D)
    E = \(E_1\) = \(E_2\) = \(E_3\)
  • 98
    Given that SQ = 10cm and SR = 6cm, the refractive index of the block of glass shown in the above figure is
    Απάντηση
    (A)
    1.67
  • 99
    Water waves and light waves differ generally in their
    Απάντηση
    (D)
    medium of propagation
  • 100
    A method of demagnetization is
    Απάντηση
    (C)
    heating a magnetic bar red hot and allowed to cool e-w direction