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WAEC - Physics (2001)

  • 1
    Which of the following physical processes cannot be explained by the molecular theory of matter?
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    (C)
    radiation of heat
  • 2
    A spring balance,which is suspended from the roof of a lift, carries a mass of 1kg at its free end. If the lift accelerates upwards at 2.5ms-2, determine the reading on the spring balance. [g = 10ms-2]
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    (B)
    12.5N
  • 3
    An object weight 10N immersed in a liquid displaces a quantity of the liquid. If the liquid displaced weighs 6N, determine the upthrust of the object
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    (C)
    6N
  • 4
    Which of the following statements about pressure is not correct? pressure
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    (A)
    increases with an increase in surface area
  • 5
    The apparent weight of a body fully 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-2]
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    (B)
    6.4 x 10-3m3
  • 6
    A block weighing 15N rests on a flat surface and a horizontal force of 3N is exerted on it. Determine the friction force on the block
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    (C)
    3.0N
  • 7
    Which of the following equations represents the distance x, travelled by a body moving on a straight road with a constant speed? [The other symbol have their usual meanings]
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    (B)
    x = Ut
  • 8
    The amplitude of the motion of a body performing simple harmonic motion decreases with time because
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    (A)
    friction force dissipate the energy of motion
  • 9
    The amplitude of a particle executing simple harmonic motion in 5cm while its angular frequency is 10 rad s-1. calculate the magnitude of the maximum acceleration of the particle
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    (D)
    5.00ms-2
  • 10
    The time rate of change of momentum is
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    (B)
    force
  • 11
    Which of the following statements about elastic collision is correct?
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    (C)
    both kinetic energy and momentum are conserved
  • 12
    Electrical resistance is a property of an electrical energy to be converted into
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    (B)
    heat energy
  • 13
    A simple machine with an efficiency of 75% lifts a load of 5000N when a force of 500N is applied to it. Calculate the velocity ratio of the machine
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    (B)
    13.3
  • 14
    A screw jack with a Tommy bar of length 12cm is used to raise a car through a vertical height of 25cm by turning the Tommy bar through 50 revolutions. Calculate the approximate velocity ratio of the jack [\(\pi = 3.142\)]
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    (D)
    151
  • 15
    a beam PQ pivoted at P carries a load of 80N as shown above. Calculate the effort E, required to keep it horizontal. [neglect the weight of the beam]
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    (D)
    13.3N
  • 16
    A resistance thermometer has a resistance of 20\(\Omega\) at 0oC and 85\(\Omega\) at 100oC. If its resistance is 52\(\Omega\)in a medium, calculate the corresponding temperature
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    (A)
    49.2oC
  • 17
    A given mass of an ideal gas has a pressure of 500Nm-2 at -13ºC. If its volume remains constant. Calculate its pressure at 247ºC.
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    (D)
    1000Nm-2
  • 18
    The volume of an ideal gas at a pressure of 77cmHg and temperature 60oC is 24cm3. If the temperature and pressure are increased to 98oC
    and 81cmhg respectively, calculate the new volume of the gas
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    (C)
    254.2cm3
  • 19
    The amount of heat given out or absorbed when a substance changes its state at a constant temperature is known as
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    (A)
    latent heat
  • 20
    Which of the following physical qualities affects the saturated vapour pressure of a liquid ?
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    (A)
    temperature
  • 21
    Humidity is used to describe the amount of
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    (D)
    water vapour in the amosphere
  • 22
    Surface waves travelling in deep water at 15ms-1 are incident at a shallow water boundary. If the angles of incidence and refraction are 45o and 30o respectively. Calculate the speed of the waves in shallow water
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    (C)
    10.6ms-1
  • 23
    An incident ray is reflected normally by a plane mirror onto a screen where it forms a bright spot. The mirror and screen are parallel and 1m apart. If the mirror is rotated through 5o, calculate the displacement of the spot
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    (D)
    17.6cm
  • 24
    Convex spherical mirrors are preferred to plane mirrors as driving mirrors because
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    (B)
    it provides a wider field of view
  • 25
    An object is placed 20cm from a lens. If an image is formed on a screen 260cm away from the lens, calculate the magnification of the image
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    (D)
    13
  • 26
    A piece of cloth appears green in sunlight. When held in red light, it will appear
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    (D)
    black
  • 27
    Dispersion of white light by a glass prism occurs because
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    (B)
    the refractive index of glass is different from each constituent colour of white light
  • 28
    Which of the following statements about sound is correct?
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    (C)
    the wavelength of sound changes when it travels from to water
  • 29

    The diagram above shows the wire of a sonometer box set into resonance by a vibrating tuning fork of frequency f, when the wire is stretched by a tension T, the resonating length of the wire is I while the wavelength of the sound produced is \(\lambda\). Which of the following statements is not correct? The wave produced on the wire is

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    (A)
    stationary and lonitudinal
  • 30
    The diagram above shows the wire of a sonometer box set into resonance by a vibrating tuning fork of frequency f, when the wire is stretched by a tension T, the resonating length of the wire is I while the wavelength of the sound produced is \(\lambda\). Which of the following statements about the frequency of vibration of the wire is not correct?
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    (A)
    proportional to the mass per unit length of the wire
  • 31
    If the frequency of the tuning fork at resonance is 256Hz, calculate the frequency of vibration of the wire when the tension in he wire is increased to 196N
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    (C)
    358.4Hz
  • 32
    The magnitude of the gravitational force between two particles 0.10m apart is 10N. If the distance between them is increased to 0.20m, calculate the magnitude of the new force
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    (D)
    2.5N
  • 33
    As the plates of a charged variable capacitor are moved closer together, the potential difference between them
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    (B)
    decrease
  • 34
    What is the effective capacitance in the circuit?
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    (A)
    2\(\mu F\)
  • 35
    What is the total energy stored by the capacitors?
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    (D)
    1.0 x 10-2J
  • 36
    Three identical lamps each power 100W are connected in parallel across a potential difference of 250V. Calculate the current in the circuit
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    (C)
    1.2A
  • 37
    An electric bulb is rated 60W, 220V. Calculate the resistance of its filament when it is operating normally
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    (D)
    806.7\(\Omega\)
  • 38
    The Earth's magnetic equator passes through Jos in Nigeria. At Jos. the
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    (C)
    angle of dip is zero
  • 39
    Which of the following statements about magnetic lines of force is not correct?
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    (C)
    magnetic lines of force are closely packed together at neutral point
  • 40
    The material used for constructing the core of an electromagnet is
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    (A)
    iron