The ice and steam points of mercury-in-glass thermometer of centigrade scale and of uniform bore correspond respectively to 3cm and 19cm lengths of the mercury thread when the length is 12cm, the temperature is
Answer
(C)
56oC
2
A vapour is said to be saturated when?
Answer
(B)
a dynamic equilibrium exists between the liquid molecules and the vapour molecules at a given temperature
3
The latent heat of fusion of a substance is the heat required to
Answer
(C)
change unit mass of substance from solid to liquid at constant temperature
4
The following types of waves are transverse EXCEPT
Answer
(C)
sound waves
5
The principle of transmissibility of pressure in a fluid at rest in all directions is known as
Answer
(D)
Pascal's law
6
When fixed mass of an ideal gas expands at constant temperature, which property of the gas molecule increases?
Answer
(D)
average seperation
7
Which of the following does NOT describe the image formed by a plane mirror?
Answer
(D)
magnified
8
If a source of sound is moving, a stationary listener will hear a sound of different frequency. This is called
Answer
(A)
Doppler effect
9
Which of the following elements are real magnetic materials?
Answer
(A)
Iron, steel and nickel
10
An inclined plane of angle \(\theta\), acting as a simple machine, has a velocity ratio
Answer
(B)
\(\frac{1}{\text{sin}\theta}\)
11
Heat may be transferred by conduction, convection and radiation. By which of these methods does heat travel through vacuum?
Answer
(C)
radiation only
12
Which of the following statements is applicable to a real image formed by a concave mirror? i. it can be observed on a screen ii. it is always inverted and in front of the mirror iii. it only seams to exist IV. it is formed by the actual converging of rays of light
Answer
(B)
i, ii and iv only
13
Which of the following is NOT an effect that can be produced by an electric current?
Answer
(E)
none of the above
14
A cell of e.m.f 2V and internal resistance 1\(\Omega\) supplies a current of 0.5 amps to a resistance whose value is
Answer
(E)
3\(\Omega\)
15
An example of a scalar quantity is
Answer
(C)
electric charge
16
Heat was supplied to a block of ice at 0oC until half of it melted. Which of the following statements is true?
Answer
(B)
the temperature remains constant and the volume of the ice decreases
17
When a ray of light passes from water to glass, it is
Answer
(B)
bent towards the normal
18
The resistance of a 240V, 60 watt electric filament bulb is
Answer
(E)
960\(\Omega\)
19
An aircraft travelled from calabar to kano as follows: it flew first to ilorin convering a distance of 300km, 30o west of North, and then flew 400km, 60o East of North to kano. What is the resultant displacement?
Answer
(D)
500km
20
All of the following frequencies are overtones of 320 Hz EXCEPT
Answer
(C)
520Hz
21
The driver in a motor car, of which the total mass is 800kg and which is traveling at 20ms-1, suddenly observes a stationary dog in his path 50m ahead. If the car brakes can exert a force of 2000N, what will most likely happen?
Answer
(B)
the car will stop 30m after hitting the dog
22
The absolute refractive indices of glass and water are \(\frac{3}{2}\) and \(\frac{4}{3}\) respectively. The refractive index at the interface when a ray travels from water to glass is
Answer
(C)
\(\frac{9}{8}\)
23
Which of the following statements is CORRECT?
Answer
(C)
the magnitude of any charge is a multiple of the charge of an electron
24
Which type of radiation does not NOT originate within the nucleus?
Answer
(E)
x-rays
25
Which type of radiation does not NOT originate within the nucleus?
Answer
(E)
x-rays
26
The resistance of an open series circuit is
Answer
(E)
infinite
27
The lack of power of accommodation which is mainly due to the hardening of the eye lens and is usual with onset of old age is called?
Answer
(C)
presbyopia
28
A body falls freely under gravity (g = 9.8ms-2) from a height of 40m on to the top of a platform 0.8m above the ground. Its velocity on reaching the platform is
Answer
(E)
27.7ms-1
29
Alternating current can induce voltage because it has a
Answer
(B)
varying magnetic field
30
Two particles X and Y starting from rest cover the same distance. The acceleration of X is twice that of Y. the ratio of the time taken by X to that taken by Y is
Answer
(C)
\(\frac{1}{\sqrt2}\)
31
a balloon inflated with helium gas at ground level is released. As it rises through a constant temperature atmosphere.
Answer
(B)
te product of pressure and volume remains constant
32
Change of state is accompanied by change of?
Answer
(E)
volume and heat content
33
The quantity (timbre) of sound depends on
Answer
(C)
harmonics
34
The mass of a proton is approximately equal to that of
Answer
(E)
a neutron
35
An object placed on the principle axis of a convex lens of focal length 10m produces a real image of double magnification. The image distance from the lens is
Answer
(A)
30cm
36
A liquid-in-glass thermometer should quickly register temperature changes. This is achieved by choosing a liquid that
Answer
(D)
has a high thermal conductivity
37
The extension in a spring when 5g wt was hung from it was 0.56cm. If Hooke's law is obeyed, What is the extension caused by a load of 20g wt?
Answer
(E)
2.24cm
38
Which of the following is NOT directly associated with direct current (DC)?
Answer
(C)
a transformer
39
The relationship between the period T and the length l of a simple pendulum is T = 2\( \pi \) \( ( \frac{I}{g}) ^{ \frac{1}{2} } \). From experiment data of T and I, one can obtain the following graphs, i. T vs.I ii. T vs I2 iii. T2 vs. I iv. T vs \( \sqrt{I} \) v. logT vs logI. Which of the following graphs, are linear?
Answer
(D)
iii, iv and v
40
A transformer has 300 turns of wire in the primary coil and 30 turns in the secondary coil.If the input voltage is 100 volts, the output voltage is
Answer
(B)
10 volts
41
A closed coil of wire is placed near a magnet. The magnet lies along the axis of the coil. Under which of the following conditions would there be no current in the coil?
Answer
(D)
when both the coil and the magnet are held stationary
42
If I is the current passing through a metallic resistor and H is the rate of Heat generated in the resistor at a constant temperature, then
Answer
(D)
H \(\alpha\) I2
43
A solid weighs 4.8g in air, 2.8g in water and 3.2g in kerosine. The ratio of density of the solid to that of the kerosine is
Answer
(B)
3
44
A body of mass 6kg rests on an inclined plane. The normal reaction is R and the limiting frictional force is F as shown in the image above. if F = 30N, and g = 10ms2 then the angle of inclination \( \theta \) is
Answer
(B)
\( 30^{\circ} \)
45
The effect of closing the key K in the circuit shown above would be to
