Which of the following statements about the mass and the weight of a body is not correct? its
Respuesta
(D)
weigh at the equatior and at the poles is the same
3
An object weighs 60.0N in air, 48.2N in a certain liquid X, and 44.9N in water, Calculate the relative density of X
Respuesta
(D)
0.782
4
Calculate the change in volume when 90g of ice is completely melted. [density of water = 1g cm-3, density of ice = 0.9cm-3]
Respuesta
(C)
10.00cm3
5
The diagram above represent displacement D, versus time, t graph of a progressive wave. Deduce the frequency of the wave
Respuesta
(B)
10 Hz
6
Which of the following concept is not an evidence of the particle nature of matter?
Respuesta
(D)
crystallization
7
A diver is 5.2m below the surface of water of density 1000Kgm-3. If the atmospheric pressure is 1.02 x 105pa. Calculate the pressure on the diver [g = 10ms-2]
Respuesta
(C)
1.54 x 105 pa
8
A steel needle floating on water, sinks when kerosine is added to the water. This is because the kerosine
Respuesta
(C)
reduces the surface tension of the water
9
On which of the following factor does the viscosity of a liquid depend? i. Nature of the liquid. ii. Temperature of the liquid. iii. Area of the liquid surface
Respuesta
(A)
i and ii only
10
An elastic string of force constant 200N m-1 is stretched through 0.8m within its elastic limit. Calculate the energy stored in the string
Respuesta
(A)
64.0J
11
A machine of velocity ratio 5 is used in lifting a load with an effort of 500N. If the machine is 80% efficient. Determine the magnitude of load
Respuesta
(B)
2000N
12
The speed of an object in rectilinear motion can be determine from the
Respuesta
(C)
slope of a distance-time graph
13
A body is said to be moving with uniform acceleration if it experiences equal
Respuesta
(A)
increase in velocity at equal time intervals
14
A body is dropped from a certain height above the ground level, falls with uniform
Respuesta
(C)
acceleration
15
A body of mass 8kg moving with a speed of 30ms-1 is brought to rest in 2.5s by a constant retarding force. Calculate the magnitude of the force
Respuesta
(B)
96N
16
A force acting on a body causes a change in the momentum of the body from 12kg ms-1 to 16kg ms-1 in 0.2s. calculate the magnitude of the force
Respuesta
(B)
20.0N
17
The bob of a single pendulum has a mass of 0.02kg. Determine the weight of the bob [g = 10ms-2]
Respuesta
(B)
0.20N
18
A ball bearing is projected vertically upwards from the ground with a velocity of 15ms-1. Calculate the time taken by the ball to return to the ground [g = 10ms-1]
Respuesta
(B)
3.0s
19
A loaded spring performs simple harmonic motion with an amplitude of 5cm. If the maximum acceleration of the load is 20cm s-1, calculate the angular frequency of the motion
Respuesta
(A)
2 rad s-1
20
When compared with water, mercury is preferred as a thermometric liquid because
Respuesta
(B)
has lower specific heat capacity
21
Which of the following values on the absolute scale of temperature is the ice point?
Respuesta
(D)
273k
22
On a cold day, a concrete floor feels colder to the bear foot then a mat on the same floor because the
Respuesta
(D)
concrete floor is a better conductor of heat than the mat
23
When a metal ball is heated through 30oC,its volume becomes 1.0018cm3. If the linear expansivity of the material of the ball is 2.0 x 10-5 K-1, calculate its original volume
Respuesta
(A)
1.0000cm3
24
A faulty barometer reads 72.6cm Hg when the atmospheric pressure is 75.0cm Hg. Calculate the atmospheric pressure when the barometer reads 72.0cn Hg
Respuesta
(B)
74.38cm Hg
25
On a basis of the kinetic theory, an increase in the temperature of a fixed volume of an ideal gas causes
Respuesta
(C)
an increase in the average speed of the gas molecules
26
The temperature of 900cm3 of an ideal gas at a pressure of 114cm Hg is 27oC. Calculate its volume at 76cm Hg and 0oC
Respuesta
(D)
1228.5cm3
27
The basic difference between a transverse wave and a longitudinal wave travelling in the same direction in a medium is in the
Respuesta
(C)
direction of vibration of the particles of the medium
28
A wave travelling from water to glass suffers a change in its speed at the common boundary. Which of the following properties explains this observation?
Respuesta
(B)
refraction
29
The image of an optical pin placed at the principal focus of a concave mirror will be formed
Respuesta
(D)
at infinity
30
A man 1.8m tall stands 3m away from a pin hole camera. If the distance between the pin hole and the screen of the camera is 0.3m. Calculate the height of the image of the man produced by the camera
Respuesta
(A)
0.18m
31
During a thunderstorm, lightning and thunder occurred simultaneously in the atmosphere. An observer on the earth surface's sees the lightning flash shortly before hearing the thunder. This is because the
Respuesta
(B)
speed of sound is less than that of light
32
A magnified and virtual image of a near object is produced by
Respuesta
(D)
simple microscope
33
A girl stand 80m away from a tall cliff and blows a whistle. If the speed of sound in air is 330ms-1, how long would it take for her to hear the echo of the sound?
Respuesta
(C)
0.485s
34
Which of the following reasons explains why the walls and ceilings of a standard concert hall are usually covered with perforated pads? To
Respuesta
(C)
reduce the effect of revibration of sound waves
35
The sound from a vibrating tuning sound is when the tip of its stem is placed on a wooden table than when in air because
Respuesta
(D)
a large mass of air is set into vibration by the table
36
Charges on a conductor are
Respuesta
(D)
generally concentrated at sharply curved surface
37
Which of following functions is performed by manganese IV oxide in the Lenclanche cell?
Respuesta
(B)
depolarisation of the cell
38
A car fuse marked 3A operates optimally on a 12V battery, calculate the resistance of the fuse
Respuesta
(D)
4.0\(\Omega\)
39
Find the cost of running a 60W lamp for 24 hours. If 1kW hr cost 5 naira
Respuesta
(C)
7.2 naira
40
The quantity of electric charge stored in a capacitor is measured in
Respuesta
(C)
coulomb
41
Calculate the energy stored in a 20\(\mu F\) capacitor. If the p.d between the plates is 40V
Respuesta
(B)
1.6 x 10-2J
42
Given that the gravitational constant is G. Newton's universal law of gravitation states that the force of attraction between two masses M1 and M2 separation by a distance r is
Respuesta
(C)
\(\frac{GM_1 M_2}{r^2}\)
43
A charge of 1.6 x 10-10C is placed in a uniform electric field of intensity 2.0 x 105 NC-1. calculate the magnitude of the electric force exerted on the change
Respuesta
(C)
3.2 x 10-5N
44
Which of the following statements is not correct?
Respuesta
(C)
magnetic fields are scalar quantities
45
The main function of the mouth piece of a telephone is that it converts sound energy to
Respuesta
(B)
electrical energy
46
An atom is normally electrically neutral because the
Respuesta
(A)
number of electrons is equal to the number of protons
47
In which of the following devices is the principle of photoelectric effect not applicable?
Respuesta
(D)
periscope
48
Which of the following statements about X-rays is not correct? They
Respuesta
(D)
are produced from the nucleus of an atom
49
A radioactive substance has a half-life of 3 days. If a mass of 1.55g of this substance is left after decaying for 15 days, determine the original value of the mass
Respuesta
(A)
49.6g
50
Which of the following representations is correct for an atom X with 28 electrons and 30 neutrons?
