A ball falling through a viscous liquid is acted upon by
답변
(D)
upthrust, the ball's weight and viscous force
2
An object of mass m moves with a uniform speed v round a circular path of radius r. If its angular speed is \(\omega\), the magnitude of the centripetal force acting on it is
답변
(A)
\(m \omega^2 r\)
3
When an elastic material is stretched by a force, the energy stored in it is
답변
(B)
potential
4
When the linear momentum of a body is constant, the net force acting on it
답변
(A)
is zero
5
If no net force acts on an object, the object maintains a state of rest or constant speed in a straight line. The above is a statement of Newton's
답변
(A)
first law of motion
6
Which of the following pairs of physical quantities is made up of vectors?
답변
(C)
dislacement and acceleration
7
The knowledge of surface tension is applied in the following areas except in
답변
(B)
production of palm oil
8
A body is projected vertically upwards with a speed of 10 ms-1 from a point 2m above the ground. Calculate the total time taken for the body to reach the ground. [g = 10ms-2]
답변
(B)
2.00s
9
A car starts from rest and covers a distance of 40m in 10s. Calculate the magnitude of its acceleration
답변
(B)
0.80ms-2
10
The diagram above illustrates a uniform metre rule which is balanced on a pivot by some masses. Calculate the value of M
답변
(D)
25.0g
11
The period of a simple pendulum X is 5s. What is the period of a simple pendulum Y which makes 50 vibrations in the same time it takes X to make 20 vibrations?
답변
(C)
2.0s
12
Alcohol of mass 21g and density 0.7g cm-3 is mixed with 10g of water. Determine the density of the mixture [density of water = 1.0gcm-3]
답변
(A)
0.775gcm-3
13
A device that converts mechanical energy into electrical energy is
답변
(A)
a dynamo
14
The S.I unit of power is
답변
(C)
W
15
A screw-jack has the distance between its successive threads as P and the length of its tommy bar as r. Its velocity ratio is given by the expression
답변
(B)
\(\frac{2 \pi r}{P}\)
16
Heat transfer by conduction is similar to wave motion because
답변
(D)
no transfer of materials is involved
17
The temperature at which the water vapor in the air saturates the air and begins to condense is known as
답변
(A)
dew point
18
The change of state from solid to liquid occurs
답변
(A)
at constant temperature
19
Which of the following types of thermometers can be used to measure a range of temperature from -50°C to 50°? i. Clinical ii. Mercury iii. Alcohol-in-glass
답변
(C)
iii only
20
A body of mass M kg rests on a plane inclined at an angle \(\theta\) to the horizontal. The component of the weight of the body parallel to the plane is
답변
(A)
Mg sin \(\theta\)
21
A quantity of water at 20oC is mixed with another quantity of water at 70oC. The final steady temperature of the mixture is 40oC. Determine the ratio of the mass of the cold water to that of the hot water
답변
(B)
3:2
22
The mass of an empty density bottle is 30g. When filled with a liquid, the mass of the bottle and the liquid is 40g. On heating the filled bottle through 40ºc, the mass reduces to 38g. Calculate the apparent cubic expansivity of the liquid
답변
(B)
6.25 x 10-3K-1
23
A car traveling at 30ms\(^{-1}\) overcomes a frictional resistance of 100N while moving. Calculate the power developed by the engine. [1 hp = 0.75 kW]
답변
(C)
4.00hp
24
The quality of a note depends on its
답변
(C)
overtones
25
A transverse wave can be distinguished from a longitudinal wave by
답변
(D)
polarization
26
Refraction of lights differs from reflection in that, in refraction i. at least two media are involved ii. there is a change in the direction of the ray iii. the speed of the ray changes. Which of the statements above is/are correct?
답변
(D)
i and iii only
27
Which of the following relations about the focal length fo of the objective and focal length fe of the eye piece of a compound is correct?
답변
(B)
fo < fe
28
The functional difference between a lens and a mirror is that a lens
답변
(B)
refracts a beam of light while a mirror reflects it
29
The diagram above illustrates an electromagnetic wave travelling with speed 3.0 x 108ms-1. Calculate the wave length of the wave
답변
(C)
0.16m
30
A fish inside a pond appears to be at a depth of 1.5m when viewed vertically from above. The refractive index of the water in the pound is 1.3. Calculate the apparent displacement of the fish
답변
(D)
0.45m
31
an observer hears an echo 1.26 seconds after blowing a whistle near a cliff. calculate the distance of the observer from the cliff. [speed of sound in air = 330ms-1]
답변
(B)
207.9m
32
An object is placed in front of two plane mirrors inclined at 60o to each other. Determine the number of the images formed
답변
(C)
5
33
An ammeter can be adapted to measure potential difference by using a
답변
(B)
multiplier
34
The region around a magnet in which magnetic force can be expressed is known as
답변
(C)
field
35
In an ac circuit when the supply voltage frequency is equal to the resonant frequency, the current
답변
(D)
is in phase with the supply voltage
36
The energy stored in a simple cell is
답변
(D)
chemical
37
Which of the following conditions occur at resonance in a series RLC circuit? i. Impedance equals resistance ii. Current is maximum iii. Reactance is maximum iv. Current and voltage are 90° out of phase
답변
(A)
i and ii only
38
An electric motor converts
답변
(A)
electrical energy to mechanical energy
39
A 15 \(\mu F\) capacitor is connected to a 240V, 50Hz ac. source. Calculate the reactance of the capacitance [\(\pi = 3.142\)]
답변
(D)
212\(\Omega\)
40
Two identical charges situated 20cm apart in vacuum repel each other with a force of 1.0N.Calculate the value of each other with a force of 1.0N. Calculate the value of each charge. [(14 \(\pi \varepsilon_o)^{-1}\) = 9 x 109Nm2C-2]
답변
(A)
21\(\mu C\)
41
In the circuit diagram above, E is a battery of negligible internal resistance. If its emf is 9.0V. Calculate the current in the circuit ``
답변
(B)
1.0A
42
A wire of length 100 cm has a resistance of 10\(\Omega\). If its cross-sectional area is 0.005cm2, determine its resistivity
답변
(A)
0.0005\(\Omega\)cm
43
A transformer has 400 turns of wire in the primary coil and 40 turns in the secondary col. If the input voltage is 150 volts. Calculate the magnitude of the output voltage
답변
(D)
15V
44
The circuit above illustrates a standard resistor R, voltage source E and a lamp L connected in series. If the temperature of R is increased, the brightness of the lamp will
답변
(B)
decrease slightly
45
The energy required to separate the nucleus in an atom completely is known as
