WAEC - Physics (1989)

  • 1
    Which of the following is NOT a vector quantity?
    Хариулт
    (D)
    temperature
  • 2
    Which of the following is not a consequence of a force field?
    Хариулт
    (B)
    surface tension
  • 3
    A boy pulls a nail from the wall with a string tied to the nail. The string is inclined at an angle of 60o to the wall. If the tension in the string is 4N, what is the effective force used in pulling the nail?
    Хариулт
    (A)
    2√3 N
  • 4
    Which of the following is used to determine the relative density of the acid in a car battery?
    Хариулт
    (D)
    Hydrometer
  • 5
    A block of material of volume 20cm-3 and density 2.5gcm-3 is suspended from a spring balance with half the volume immersed in water. What is the reading of the spring balance? (Density of water = 1.0gcm-3).
    Хариулт
    (D)
    40g
  • 6
    A piece of cork floating on water is acted upon by the forces of...
    Хариулт
    (B)
    weight and upthrust
  • 7
    A stone tied to a string is made to revolve in a horizontal circle of radius 4m with an angular speed of 2 rad per sec. With what tangential velocity will the stone move off the circle if the string is cut?
    Хариулт
    (B)
    8.0 ms-1
  • 8
    The motion of the prongs of the sounding tuning fork is
    Хариулт
    (D)
    vibratory
  • 9
    Which of the following is a derived unit?
    Хариулт
    (B)
    Coulomb
  • 10
    An engine raises 1000kg of water through a height of 60m in 20s. What is the power of the engine? (Take g = 10ms-2>).
    Хариулт
    (B)
    30,000 W
  • 11
    A thermometer has its stem marked in millimeter instead of degree Celsius. The lower fixed point is 30mm and the upper is 180mm. Calculate the temperature in degree celsius when the thermometer reads 45mm.
    Хариулт
    (E)
    10.0oC
  • 12
    Which of the following surfaces will radiate heat energy best?
    Хариулт
    (C)
    Black
  • 13
    Which of the followiempeng statements is/are not correct?
    Хариулт
    (E)
    The boiling point of a liquid is not affected by impurities
  • 14
    Water in an open container boils at a lower temperature when heated at the top of a mountain than at sea-level because at the top of a mountain the
    Хариулт
    (D)
    pressure is lower than that at sea-level
  • 15
    Which of the following substance is not a good conductor of electricity?
    Хариулт
    (B)
    Glass
  • 16
    Calculate the heat energy required to vapourize 50g of water initially at 80oC if the specific heat capacity of water is 4.2Jg-1K (specific latent heat of vapourization of water is 2260Jg-1).
    Хариулт
    (C)
    117200J
  • 17
    A block of ice at its melting point is left on a table in the atmosphere and observed to melt gradually. Which of the following statements is true about the melting process?
    Хариулт
    (E)
    the ice block absorbs heat from the atmosphere and its temperature remains constant as it melts
  • 18
    All the heat generated by a current of 2A passing through a resistor of 6Ω for 25s is used to evaporate 5 g of a liquid at its boiling point. What is the specific latent heat of the liquid?
    Хариулт
    (B)
    120 Jg-1
  • 19
    Which of the following instruments can be used to compare the relative magnitudes of charges on two given bodies?
    Хариулт
    (D)
    Gold leaf electroscope
  • 20
    A short chain is usual attached to the back of a petrol tanker trailing behind it to ensure that the
    Хариулт
    (C)
    charges generated by friction in the tanker can be conducted to the earth
  • 21
    A ray of light is incidence on a plane mirror at an angle of 35o. What is the angle by the reflected ray with the surface of the mirror?
    Хариулт
    (D)
    55o
  • 22
    The image in a pine-hole camera is always
    Хариулт
    (D)
    inverted
  • 23
    The refractive index of a given transparent medium is 1.4. Which of the following is the minimum internal angle for total internal reflection to take place in the medium?
    Хариулт
    (D)
    46o
  • 24
    The distance between a node and an anti-node for a transverse wave is equal to
    Хариулт
    (D)
    one-quater of the wavelength
  • 25
    Which of the following is a stringed instrument?
    Хариулт
    (C)
    piano
  • 26
    A sound pulse sent vertically downwards into the earth is reflected from two different layers of the earth such that echoes are heard 1.2s and 1.4s. Assuming speed of the pulse is 2000ms-1, calculate the distance between the layers.
    Хариулт
    (A)
    200 m
  • 27
    In a wave the maximum displacement of particles from their equilibrium positions is called.
    Хариулт
    (B)
    amplitude
  • 28
    A string is stretched between two points 50cm apart. It is then plucked at its center and the velocity of the wave produced is 300m/s. Calculate the number of vibrations made by the string in 1s.
    Хариулт
    (D)
    300
  • 29
    Which of the following is not a property of longitudinal waves?
    Хариулт
    (D)
    polarization
  • 30
    What is the gravitational potential due to a molecule of mass, m and at a distance, r from it? (G = gravitational constant).
    Хариулт
    (B)
    Gm/r