A tuber of cassava can be processed into powder. This explains the face that
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(D)
matter is made up of tiny particle
2
A piece of metal of relative density 5.0 weighs 60N in air. Calculate its weight when fully immersed in water
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(C)
48N
3
The tendency of a body to remain at rest when a force is supplied to it is called
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(C)
inertia
4
A force acts on a body for 0.5s changing its momentum from 16.0kg ms-1 to 21.0kgms-1, calculate the magnitude of the force
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(D)
10.0N
5
A moving object is said to have a uniform acceleration if its
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(C)
velocity increases by equal amount in equal time intervals
6
The period of an oscillatory motion is defined as the
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(C)
time to complete one oscillation
7
The mass on a loaded spiral spring oscillates vertically between two extreme positions P and R equidistant from the equilibrium position Q. Which of the following statements about the system is not correct
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(D)
the total energy of the system is always constant
8
A ball f mass 5.0kg hits a smooth vertical wall normally with a speed of 2ms-1. Determine the magnitude of the resulting impulse
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(B)
10.0kgms-1
9
Which of the following statements correctly defines a simple machine? a device
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(C)
with which work can be done easily
10
A platinum resistance thermometer has a resistance 4\(\Omega\) at 0oC and 10\(\Omega\) at 100oC. Assuming the resistance changes uniformly with temperature. Calculate the resistance of the thermometer when the temperature is 45oC.
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(B)
6.7\(\Omega\)
11
A metal rod of length 100cm is heated through 100ºC, calculate the change in length of the rod [linear expansivity of the material of the rod is 3 x 10\(^{-5}\)K\(^{-1}\)]
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(B)
3mm
12
The heat capacity of a calorimeter is the amount of energy required to
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(C)
change the temperature of the calorimeter
13
Which of the following statement about latent heat of vaporization is correct? It
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(B)
breaks completely the force of attraction completely between the molecules of a liquid
14
When the pressure of a fixed mass of gas is doubled at constant temperature, the volume of the gas is
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(D)
halved
15
The volume of a given mass of an ideal gas at 327k and 9.52 x 104 Pa is 40cm3. calculate the volume of the gas at 273k and 1.034 x 105Pa.
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(D)
30.75cm3
16
A wave of weight length 0.30m travels 900m in 3.0s, calculate its frequency
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(C)
1000Hz
17
Which of the following condition is necessary for the occurrence of total internal reflection of light?
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(C)
the angle of incidence must be greater than the critical angle
18
The image which cannot be formed on a screen is said to be
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(D)
virtual
19
An object is placed on the principal axis and at the centre of curvature of a concave mirror, the image of the image formed by the mirror is
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(B)
real and inverted
20
A converging lens produces an image four times as large as an object placed 25cm from the lens. Calculate its focal length
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(D)
20cm
21
The horizontal floor of a water reservoir appears to be 1.0m deep when viewed vertically from above. If the refractive index of water is 1.35, calculate the real depth of the reservoir
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(B)
1.35m
22
A converging lens has a focal length of 5cm. Determine its power
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(A)
+20.0
23
Which of the following pairs of rays shows the widest separation in the spectrum of white light?
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(B)
orange and indigo
24
Which of the following statements about the human eye and the camera is correct?
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(C)
the inside of both of them is blackened to absorb unwanted light
25
The speed of sound in air is is directly proportional to
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(D)
the square roor of its temperature on the absolute scale
26
A sonometer wire of linear density 0.08kg m-1 subjected to a tension of 800N is plucked. Calculate the speed of a pulse which moves from one end of the wire to the other
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(B)
100.0ms-1
27
Which of the following instruments gives a pure note when sounded?
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(C)
tunning fork
28
Which of the following features of an electrostatic line of force is not correct?
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(D)
it can cross another line of force in a region of intense electric field
29
Which of the following statement about force is correct ?
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(C)
fields are real but their corresponding field lines are imaginary
30
A positively charged glass rod is placed by near the cap of a positively charge electroscope. The divergence of the leaf is observed to
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(B)
increase
31
Two identical cells each of e.m.f 2v and internal resistance 1.0\(\Omega\) are connected in parallel. The combination is connected to an external load of 1.5\(\Omega\). Calculate the current in the circuit
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(B)
1.00A
32
Which of the following factors does not affect the the electric resistance of a wire?
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(B)
mass
33
A current of 10A passes through a conductor for 10s, calculate the charge flowing through the conductor
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(A)
100.0C
34
A lamp is rated 240V 60W, calculate the resistance of its filament
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(C)
960\(\Omega\)
35
The maximum power dissipated by a 100\(\Omega\) resistor in a circuit is 4W. Calculate the voltage across the resistor
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(B)
20V
36
One difference between a reactance and a resistance in an alternating current circuit is
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(D)
the current in a reactance is lower than in the resistance
37
The direction of induced current in a straight wire placed in magnetic field is determined by using?
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(D)
Lenz's law
38
Which of the following statements about an electromagnet is not correct?
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(D)
it has permanent poles
39
Which of the following statements is not true of the isotopes of an element? They
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(D)
have the same mass number
40
Which of the following statements is true of ultra violet radiations? It
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(C)
is an electromagnetic wave
41
A radioactive element has a decay constant of 0.077s-1, calculate its half life
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(B)
9.0s
42
The minimum energy required to remove an electron from an atom is known as
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(B)
ionization energy
43
Nuclear fission is preferred to nuclear fusion in the generation of energy because?
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(A)
very high temperature are required for fusion
44
Which of the following reactions represents nuclear fusion?
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(A)
\(^2_1H + ^2_1H \to ^3_2He + ^1_0n\)
45
The diagram above shows the resultant electric field pattern due to two electric point charges P and S. Which of the following statements is correct?
