Which of the following phenomena causes capillary of liquids in tubes of narrow bore?
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(B)
surface tension
2
Which of the following physical quantities are derived? i. Area ii. Thrust iii. Pressure iv. Mass
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(B)
i, ii and iii only
3
A block of volume 3 x 105m3 and density 2.5 x 103 kg m-3 is suspended from a spring balance with \(\frac{2}{3}\) of its volume immersed in a liquid of density 900 kg m-3. Determine the reading of the spring balance [g = 10ms-2]
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(B)
0.57N
4
A solid body will float in a liquid if its
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(A)
density is less than that of a liquid
5
An object is said to undergo oscillatory motion when it moves
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(B)
to and fro about a fixed point
6
A body is rotating in a horizontal circle of radius 2.5m with an angular speed of 5 rad s-1. Calculate the magnitude of the radial acceleration of the body
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(C)
12.50ms-2
7
A moving car of mass 800 kg experiences a frictional force of 200N. If it accelerates 2 ms-2, calculate the magnitude of the force applied to the car
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(D)
1800N
8
Uniform speed occurs when there is equal change of
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(A)
distance in equal times
9
A car accelerates uniformly from rest at 5 ms-2. Determine its speed after 10s
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(A)
50.0ms-1
10
Which of the following quantities is a vector?
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(D)
momentum
11
which of the following statements about simple harmonic motion is correct? The
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(A)
total mechanical energy is always conserved
12
A force acting on a body causes a change in the momentum of a body from 12 kg ms-1 to 16kg ms-1 in 0.25. Calculate the magnitude of the impulse
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(C)
4.0Ns
13
Which of the following source of energy is renewable?
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(C)
hydro
14
A stone of mass 2.0kg is thrown vertically upward with a velocity of 20.0 ms-1, calculate the initial kinetic energy of the stone
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(B)
400J
15
Which of the following statements about the mouth piece of a telephone is correct? It converts sound energy into
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(C)
electrical energy
16
The potential energy in an elastic string of force constant K which has been extended by X metres is expresses as
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(A)
\(\frac{1}{2}k \Box ^2\)
17
The engine of a train produces a force of 3000N when moving at 30.ms-1. calculate the power of the engine
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(C)
9.00 x 104W
18
The velocity ratio of an inclined plane, inclines at an angle \(\theta\) to the horizontal can be expressed as
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(A)
(sin \(\theta)^{-1}\)
19
A block and tackle system has six pulleys. a force of 50N applied to it lifts a load of weight W. If the efficiency of the system is 40%, calculate W
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(D)
120N
20
The sagging of overhead electrical cables is the consequence of
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(A)
linear expansivity
21
The silvered surface in a vacuum flask reduces heat loos due to
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(C)
radiation
22
How long will it take to heat 3kg of water from 28oC to 88oC in an electric kettle taking 6a from a 220V supply? [specific heat capacity of water = 4180 J kg-1K-1]
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(B)
570s
23
The amount of energy required to change a kilogram of ice in water without a change in temperature is
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(D)
specific latent heat of fusion of ice
24
A quantity of steam at 100oC condenses to water at the same temperature by releasing 6.9 x 104J of energy. Calculate the mass of the condensed steam. [specific latent heat of vaporization of eater = 2.3 x 106 J kg-1]
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(B)
3.0 x 10-2 kg
25
The temperature of a liquid falls after some of it has evaporated because
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(B)
the more energetic molecules have escaped into the atmosphere
26
The S.I units of frequency, period and amplitude of a wave are respectively
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(D)
hertz, second and metre
27
a note of frequency 2000Hz has a velocity of 400 ms-1. calculate the wavelength of the note
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(D)
0.2m
28
The eclipse of the moon occurs when the
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(B)
earth comes exactly between the moon and the sun
29
Which of the following observations cannot be explained using the rectilinear propagation of light?
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(D)
diffraction patterns of light
30
The distance between the successive crests of a wave travelling at 20ms\(^{-1}\) is 25cm. Calculate the frequency of the wave
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(D)
80.0hz
31
A ray from a fixed object is incident on a plane mirror at an angle of 20o. If the mirror is rotated through 30o by how many degree would the reflected ray rotate?
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(A)
60o
32
Which of the following distances is usually adjustable in the camera? The distance between the
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(A)
lens and the film
33
A travelling microscope is focused on a mark on a table. If a glass block of thickness 18.0cm is placed on the mark by how many centimeters will the microscope be moved upwards so as to focus the mark once again? [refractive index of glass = 1.5]
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(D)
6cm
34
In which of the following media would sound wave travel fastest?
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(C)
iron
35
Which of the following actions is necessary in order to tune a string to produce a note of an octave higher than its fundamental?
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(B)
reducing the tension by half
36
The acceleration due o gravity may be defined as the force
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(C)
with which the earth attracts one kilo-gram mass
37
An electron of mass m and charge \(\Box\) enters a uniform electric field between two metal plates P and q separated by a distance d. P is maintained at a potential V while Q is earthed. Determine an expression for the magnitude of the acceleration of electron through the field
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(A)
\(\frac{eV}{md}\)
38
Which of the following factors does not affect the capacitance of a parallel plate capacitor?
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(B)
nature of the surface of the plates
39
The equivalent capacitance of a 3\(\mu F\) capacitor and a 6\(\mu F\) capacitor connected in parallel is
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(D)
9.0\(\mu F\)
40
a cell of e.m.f. 1.5V and internal resistance 1.0\(\Omega\) is connected to two resistor of resistance 2.0\(\Omega\) and 3.0\(\Omega\) in series. Calculate the current through the resistors
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(A)
0.25A
41
An electric lamp rated 120W is used on a 240Vrms, calculate the resistance of its filament
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(A)
480\(\Omega\)
42
Which of the following statements about a bar magnet is correct?
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(D)
the magnetic properties are more pronounced at points near the end of the bar
43
The force experienced by a current-carrying conductor move in a magnetic field is employed in the working of the i. moving coil ammeter ii. electric bell iii. electric motor. Which of the statements above are correct?
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(C)
i and iii only
44
The breaking up of an atomic nucleus into the fragment of nearly equal size is known as
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(B)
nuclear fission
45
A 500kV is applied across an X-ray tube. Calculate the maximum velocity of the electrons produced [Me = 9.1 x 10-31kg, e = 1.6 x 10-19C]
