WAEC - Physics (2009)

• 1

  In which of the following states of matter do the molecules vibrate about their mean positions?

  回答

  (B)

  solids only
• 2

  Which of the following properties of a steel bar can be measured in terms of the dimension of length only?

  回答

  (D)

  volume
• 3

  In a hydraulic press, a force of 40N is applied to the smaller priston of area 10cm². If the area of the larger piston is 200cm², calculate the force obtained

  回答

  (A)

  800N
• 4

  A body of volume 0.046m³ is immersed in a liquid of density 980kgm^-3 with \(\frac{3}{4}\) of its volume submerged. Calculate the upthrust on the body. [g = 10ms^-2]

  回答

  (D)

  338.10N
• 5

  Which of the following types of types of motion will be produced when a pair of equal and opposite non-collinear parallel forces acts on a body?

  回答

  (D)

  rotational motion
• 6

  A body moving in a circle at constant speed has i. a velocity tangent to the circle ii. a constant kinetic energy iii. an acceleration directed towards the circumference of the circle. Which of the statements above are correct?

  回答

  (A)

  i and ii only
• 7

  A moving body accelerates when it?

  回答

  (A)

  changes its direction at constant speed
• 8

  The following properties of a solid are measured on earth i. weight ii. specific heat capacity iii. density. Which of the properties will hav a different value if measured in space?

  回答

  (A)

  i only
• 9

  Two forces 6N and 8N, act eastwards and northwards respectively on a body. Calculate the magnitude of their equilibrant

  回答

  (C)

  10N
• 10

  The period of a simple pendulum of length 80.0cm was found to have doubled when the length of the pendulum was increased by X. Calculate X.

  回答

  (D)

  240.0cm
• 11

  A body of mass 5kg movimg with a velocity of 30ms^-1 due east is suddenly hit by another body and changes its velocity to 50ms^-1 in the same direction. Calculate the magnitude of the impulse received.

  回答

  (A)

  100Ns
• 12

  Electric energy is measured in

  回答

  (C)

  kilowatt-hour
• 13

  A stone of mass 0.5kg is dropped from a height of 12m. Calculate its maximum kinetic energy. [g = 10ms^-1]

  回答

  (D)

  60.0J
• 14

  A machine of efficiency 80% is used to lift a box. If the effort applied by the machine is twice the weight of the box. Calculate the velocity ratio of the machine

  回答

  (B)

  0.63
• 15

  A faulty thermometer registers 102.5^oC t 100^oC. If the thermometer has no zero hour, what will it register at 55^oC?

  回答

  (D)

  56.4^oC
• 16

  A rod of initial lenght 2m at a temperature of 25^oC is heated to 80^oC. Calculate the increase in length of the rod if its linear expansivity is 4.0 x 10^-3K^-1

  回答

  (B)

  0.44m
• 17

  as a bicycle Tyre was being pumped up, it was noticed that contrary to Boyle's law the volume increased as the pressure increased. The best explanation of this is that Boyle's law is only true for

  回答

  (A)

  ideal gases
• 18

  It takes 4 minutes to boil a quantity of water using an electrical heating coil. How long will it take to boil the same quantity of water using the same coil if the current is doubled? [Neglect any external heat losses]

  回答

  (C)

  2 minutes
• 19

  When table salt is added to ice, the melting point of the ice

  回答

  (B)

  is lowered
• 20

  Which of the following is used to measure relative humidity?

  回答

  (D)

  hygrometer
• 21

  Which of the following factors affect the rate of evaporation of a liquid? i. Exposed surface area ii Temperature of the surroundings iii. Thermal capacity of the liquid iv. Relative humidity of the surroundings

  回答

  (D)

  i, ii amd iv only
• 22

  The maximum displacement of a vibrating tunning fork is its

  回答

  (A)

  amplitude
• 23

  A boat is rocked by waves of speed 30ms^-1 whose successive crest are 10m apart. Calculate the rate at which the boat recieves the waves

  回答

  (C)

  3s^-1
• 24

  Which of the following waves is not transverse

  回答

  (B)

  sound waves
• 25

  Light travelling through a small pinhole usually does not make a shadow with a distinct sharp edge because of

  回答

  (A)

  diffraction
• 26

  The angle of incidence of a ray of light on a plane mirror is 55^o. Determine the angle between the reflected ray and the mirror

  回答

  (A)

  35^o
• 27

  A concave mirror forms a magnified and errect image only when the object is placed

  回答

  (C)

  between the focus and the pole of the mirror
• 28

  A thin lens is placed 50cm from an illustrated object. The image produced has linear magnification of \(\frac{1}{4}\). Calculate the power of the lens in dioptres

  回答

  (C)

  10.0D
• 29

  Which of the following characteristics of light determines its colour?

  回答

  (B)

  wavelength
• 30

  Which of the following is not a part of the electro-magnetic spectrum?

  回答

  (D)

  alpha rays
• 31

  Sound interference is necessary to produce the phenomenon of

  回答

  (A)

  beats
• 32

  A satellite in circular motion around the earth does not have

  回答

  (B)

  a uniform velocity
• 33

  When a conductor mounted on an insulating stand is charged and left for sometime, the conductor eventually loses all its charges. This is because the

  回答

  (C)

  charges on the conductor are neutralized by opposite charges from the surrounding air
• 34

  An isolated metal sphere of radius R, carrying an electric charge Q, is situated in the medium of relative permitivity, Er. A test charge is placed at a point p, distance r from the surface of the sphere. Let Eo represent the permitivity of free space. The electric potential at p is given by the expression

  回答

  (B)

  \(\frac{Q}{4 \pi E_o E_r (R +r)}\)
• 35

  An isolated metal sphere of radius R, carrying an electric charge Q, is situated in the medium of relative permitivity, E_r. A test charge is placed at a point p, distance r from the surface of the sphere. Let E_o represent the permitivity of free space. The magnitude of the electric field intensity at P is given by the expression

  回答

  (D)

  \(\frac{Q}{4 \pi E_o E_rR^2}\)
• 36

  A resistor of resistance R is connected to a battery of negligible internal resistance. If a siilar resistor is connected in series with it the

  回答

  (B)

  total power dissipated is doubled
• 37

  A cell of e.m.f. 1.5V is connected in series with a resistor of resistance 3.0\(\Omega\). A voltmeter connected across the cell registers 0.9V. Calculate the internal resistance of the cell

  回答

  (A)

  2.0\(\Omega\).
• 38

  A wire of resistivity 4.40 x 10^-5\(\Omega\) cm has a cross sectional area of 7.50 x 10^-4 cm². Calculate the length of the wire that will be required to make a 4.0\(\Omega\) resistor

  回答

  (B)

  68.18cm
• 39

  A battery of e.m.f. 12.0V and internal resistance0.5\(\Omega\) is connected to 1.5\(\Omega\) and 4.0\(\Omega\) series resistor. Calculate the terminal voltage of the battery.

  回答

  (B)

  11.0V
• 40

  If the direction of the curent in a straight wire is reversed, the magnetic field

  回答

  (D)

  is oppositely directed