Which of the following is the most suitable for use as an altimeter?
Хариулт
(D)
An aneroid barometer
2
A body of weight W N rest on a smooth plane inclined at an angle\(\theta\)o to the horizontal. What is the resolved part of the weight in Newtons along the plane?
Хариулт
(A)
W sin\(\theta\)
3
A small metal ball thrown vertically upwards from the top of a tower with an initial velocity of 20ms-1. If the ball took a total of 6s to reach ground level, determine the height of the tower [g = 10ms-2]
Хариулт
(A)
60m
4
An object moves with uniform speed round a circle. Its acceleration has
Хариулт
(B)
constant magnitude and varying direction
5
A body of mass 100g moving with a velocity of 10.0ms-1 collides with a wall. If after collision, it moves with a velocity of 2.0ms-1 in the opposite direction, calculate the change in momentum.
Хариулт
(B)
1.2Ns
6
A spring of force constant 1500Nm-1 is acted upon by a constant force of 75N. Calculate the potential energy stored in the string
Хариулт
(A)
1.9J
7
A wheel and axle have radii 80cm and 10cm respectively. If the efficiency of the machine is 0.85, an applied force of 1200N to the wheel will raise a load of
Хариулт
(C)
8160N
8
A 20kg mass is to be pulled up a slope inclined at 30o to the horizontal. If the efficiency of the plane is 75%, the force required to pull the load up the plane is [g = 10ms-2]
Хариулт
(C)
133.3N
9
The spiral spring of a spring balance is 25.0cm long when 5N hangs on it and 30cm long, when the weight is 10N. What is the length of the spring if the weight is 3N assuming Hooke's law is obeyed?
Хариулт
(D)
23.0cm
10
The mass of a stone is 15.0g when completely immersed in water and 10.0g when completely immersed in a liquid of relative density 2.0. The mass of the stone in air is
Хариулт
(C)
20.0g
11
A pilot records the atmospheric pressure outside its plane as 63cm of Hg while a ground observer records a reading of 75cm of Hg for the atmospheric pressure on the ground. Assuming that the density of the atmosphere is constant, calculate the height of the plane above the ground. (Relative density of Hg = 13.0 and that of air = 0.00013)
Хариулт
(A)
1200m
12
In which of the following is surface tension important?
Хариулт
(B)
the floating of a dry needle in water
13
A thermometer with an arbitrary scale S, of equal division registers -30oS at the ice point and +90oS at the steam point. Calculate the Celsius temperature corresponding to 60oS
Хариулт
(D)
75.0oC
14
A brass rod is 2m long at a certain temperature. What is the length for a temperature rise of 100K, if the expansivity of brass is 18 x 10-6K-1?
Хариулт
(A)
2.0036m
15
What is the difference in the amount of heat given out by 4kg of steam and 4kg of water when both are cooled from 100ºC to 80ºC? [the specific latent heat of steam is 2,260,000Jkg\(^{-1}\), specific heat capacity of water is 4200Jkg\(^{-1}\)K\(^{-1}\)]
Хариулт
(C)
9,040,000J
16
How long does it take a 750W heater to raise the temperature of 1kg of water from 20oC to 50oC [specific heat capacity of water = 4200Jkg-1K-1]
Хариулт
(C)
168s
17
The saturated vapour pressure of a liquid increases as the
Хариулт
(C)
temperature of the liquid increases
18
The absolute temperature of a perfect gas is proportional to the average
Хариулт
(C)
kinetic energy of the molecules
19
A room is heated by means of a charcoal fire, An occupant of the room standing away from the fire is warmed mainly by
Хариулт
(B)
radiation
20
A boy timed 30 oscillations of a certain pendulum thrice and obtained 1min. 10s, 1min. 12s and 1min. 7s respectively.The mean period of oscillation of the pendulum is
Хариулт
(C)
2.32s
21
Which of the following is TRUE of light and sound waves?
Хариулт
(A)
they both transmit energy
22
The image in a pin-hole camera is
Хариулт
(D)
inverted and formed by the light from each point travelling in a straight line
23
When a plane mirror at which a ray is incident is rotated through an angle \( \theta \), the reflected ray will be rotated through
Хариулт
(C)
2\(\theta\)
24
A trough 12.0cm deep is filled with water of refractive index \(\frac{4}{3}\). By how much would a coin at the bottom of the trough appear to be displaced when viewed vertically from above the water surface?
Хариулт
(A)
3.0cm
25
In a ray diagram for a thin converging lens, a ray that is not parallel to the optic axis but passes through the optic center will
Хариулт
(A)
pass through undeviated
26
Which of the following correctly, describes the image of an object, 4cm from a diverging lens of focal length 12cm?
Хариулт
(A)
The image is virtual, 3cm in front of the lens
27
Two tuning forks of frequency 256Hz and 260Hz are sounded close to each other. What is the frequency of the beats produced?
Хариулт
(B)
4Hz
28
A man hears his echo from a nearby hill 2s after he shouted. If the frequency of his voice is 260Hz and the wavelength is 1.29m, how far away is the hill?
Хариулт
(B)
335.4m
29
When the bottom tip of a vibrating tuning fork is held in contact with a wooden box, a louder sound is heard. This phenomenon is known as
Хариулт
(C)
resonance
30
Which of the following statements is CORRECT about the earth's magnetic field?
Хариулт
(B)
the angle of declination is the angle between the magnetic meridian and the geographic meridian
31
An insulated rod when rubbed with a material acquires
Хариулт
(B)
no charge if it is made of glass and rubbed with fur
32
The function of the system of granulated carbon mixed with manganese (IV) oxide in a Letanche cell is to
Хариулт
(C)
prevent polarisation in the cell
33
A moving coil galvanometer of 300\(\Omega\) resistance gives full scale deflection for 1.0mA. The resistance R, of the shunt that is required to convert the galvanometer into a 3.0A ammeter is
Хариулт
(C)
0.10\(\Omega\)
34
Which of the following obeys Ohm's Law?
Хариулт
(D)
All metals
35
An equipment whose power is 1500W and resistance is 375 ohms would draw a current of
Хариулт
(B)
2.00A
36
To convert an alternating current dynamo into a direct current dynamo, the
Хариулт
(C)
slip rings are replaced with a split ring commutator
37
If a current carrying coil is mounted on a metal frame, the back e.m.f. induced in the coil causes
Хариулт
(B)
eddy currents
38
The electrochemical equivalent of platinum is 5.0 x 10-7kgC-1 to plate-out 1.0kg of platinum, a current of 100A must be passed through an appropriate vessel for
Хариулт
(A)
5.6 hours
39
which of the following statements are TRUE of isotopes? i. isotopes of an element have the same chemical properties because they have the same number of electrons. ii. isotopes of elements are normally separated using physical properties. iii. isotopes of an element have the same number of protons in their nuclei.
Хариулт
(B)
i and iii only
40
When an atom loses or gains a charge, it becomes
Хариулт
(B)
an ion
41
4g of a radioactive material of half-life 10 days is spilled on a laboratory floor. How long would it take to disintegrate 3.5g of the material?
Хариулт
(C)
30 days
42
In a nuclear fusion process, four protons each of mass Mp were fused to produce a nucleus X of mass Mx. Which of the following equations is CORRECT?
Хариулт
(A)
4Mp > Mx
43
Which of the following are True for \(\alpha\)-decay. i. mass number, decrease by four. ii. Atomic number decreases by two. iii. mass number does not change.
Хариулт
(A)
i and ii only
44
Which of the following phenomena is called photoelectric effect?
Хариулт
(C)
a metal absorbs quanta of light and then emits electrons
45
Find the tension T1 in the diagram above if the system is in equilibrium
