WAEC - Physics (2016)

1
The dimensions of momentum are
Απάντηση
(C)
MLT^-1
2
A student measures the volume of a liquid using a measuring cylinder. What else needs to be measured by the student in order to determine the density of the liquid?
Απάντηση
(C)
mass of the liquid
3
The diagram given, represents the graph of stress against strain for an elastic wire. The point Q on the graph is the
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(B)
breaking point
4
A ball is dropped from the top of a tower. Due to air resistance,it reaches terminal velocity. Which of the following statement(s) about its motion is/are correct? i. The acceleration of the ball is zero. ii. The net force on the ball is zero. iii. The velocity of the ball increases.
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(B)
i and ii only
5
Which of the following substances lowers the surface tension of water?
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(C)
detergent
6
An object of volume 400cm³ and 2.5gcm^-3 is suspended from a spring balance with half its volume immersed in water. Determine the reading on the spring balance. (Density of water = 1gcm^-3)
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(C)
800g
7

The diagram given illustrates a force-distance graph for the motion of a wooden block. Determine the work done on the block when moved through a distance of 5m.
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(D)
100J
8
The two person of a body undergoing a uniformly accelerated motion are (10s, 10ms^-1) and (30s, 50ms^-1). On the velocity-time graph pf the body.
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(B)
2.0ms^-2
9
At a birthday party, the celebrant pops a corked fruit wine. If the cork shoots out of the bottle at an angle of 40^o to the horizontal and travels a horizontal distance of 4.50m in 1.25s. Calculate the initial speed of the cork.
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(B)
4.7ms^-1
10
A uniform metre rule is balanced on a fulcrum placed at the 35cm mark by suspending a mass of 120g at the 10cm mark. Calculate the mass of the metre rule.
Απάντηση
(D)
200g
11
A plank is placed along the path on which a wheel barrow containing sand is pushed at a construction site to prevent it from sticking as illustrated in the diagram given. The large area of the plank prevents the wheel barrow from getting stuck by
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(C)
decreasing the pressure on the ground
12
When a body is thrown vertically upwards, its velocity at the maximum height is
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(B)
zero
13
Resonance occurs when one vibrating object causes a second object to vibrate at its own natural
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(C)
frequency
14
The mouth piece of a telephone handset converts
Απάντηση
(B)
sound energy to electrical energy
15
In the clinical thermometer, the function of the kink is to i. Prevent the back flow of mercury after use. ii. Ensure the back flow of mercury after use. iii. Maintain the thermometric property of mercury. iv. Allow the temperature attained to be read.
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(C)
i and iv only
16
Which of the following statements correctly defines the boiling point of a liquid? The temperature at which the
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(A)
saturated vapour pressure equals the atmospheric pressure
17

The diagram given is used to determine the
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(C)
upper fixed point of a thermometer
18
An aluminium rod of length 1.8m at 10°C is heated to proceed produce a difference in length of 0.007m. Calculate the temperature to which it is heated. (Linear expansivity of aluminium = 2.3 x 10\(^{-5}\)K\(^{-1}\)
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(D)
179^oC
19
A mercury-in-glass thermometer read 4cm at ice point and 29cm at steam point. Calculate the temperature when the mercury level is at 9cm
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(B)
20^oC
20
The continuous stirring in the method of mixtures to determine the specific thermal capacity of a substance ensures
Απάντηση
(B)
uniform distribution of thermal energy to all parts of the mixture
21
Which of the following statements is correct about the effect of dissolved salt on the freezing point of water?
Απάντηση
(A)
the freezing point is lowered
22
A pressurized perfume bottle is left on the window pane of a room. What happens to he gas molecules of the perfume on a sunny day? They
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(C)
move more rapidly
23
Given that v, f and \(\lambda\) are the velocity, frequency and wavelength of a wave respectively. Which of the following equations is correct?
Απάντηση
(B)
f = \(\frac{v}{\lambda}\)
24
The distance between two successive trough of a wave is 0.4m. If the frequency of the source is 825Hz, Calculate the speed of the wave
Απάντηση
(B)
330.0ms^-1
25
X-rays and infrared rays are both electromagnetic. Which common property do the waves have? Both waves
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(D)
travel at the same speed in a vacuum
26
The image formed by a concave mirror is real, inverted and magnified, when object is placed
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(D)
between the centre of curvature and the focus
27
Total internal reflection. i. is a phenomenon of refraction of light. ii. occurs when light rays travel into a denser medium. iii. occurs when the critical angle is just exceeded. iv. is a phenomenon of reflection of light. Which of the statements above are correct?
Απάντηση
(B)
i and iii only
28
Complementary colours are those which
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(D)
add-up to produce white light
29
The diagram given illustrates the waveform of a note produced by vibrations in an air column of length L. If the speed of sound in air is V, derive an expression for the frequency of the notes
Απάντηση
(D)
\(\frac{5V}{4L}\)
30
The pair of musical instruments that works on the vibration of air in pipes is
Απάντηση
(D)
flute and the trumpet
31
An astronomical telescope has objectives and eye-piece lenses of focal length 3.5m and 5cm respectively. Determine the magnifying power of the telescope when in normal adjustment
Απάντηση
(A)
70.0
32
An aluminium cable of diameter 4 x 10^-3m and resistivity 3.0 x 10^-8\(\omega\)m has a resistance of 21\(\Omega\). Calculate the length of the cable. (\(\pi = 3.14\))
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(B)
8.8 x 10³m
33
The electricity meters in houses measure energy unit consumed in
Απάντηση
(A)
kilowatt-hour
34
A man and his friend have masses 70kg and 60kg respectively. If they are seated 1.0m apart, calculate the gravitational force of attraction between them. (G = 6.67 x 10^-11 Nm² kg^-2)
Απάντηση
(B)
2.80 x 10^-7 N
35
The p.d across a parallel-plate capacitor is 10³V. If the distance between the two plates is 10cm. Calculate the magnitude of the electric field strength between the plates.
Απάντηση
(A)
1.0 x 10⁴Vm^-1
36
Two different materials, rubbed against each other acquired opposite charges when separated. This is an example of charging by
Απάντηση
(B)
friction
37
Two different materials, rubbed against each other acquired opposite charges when separated. This is an example of charging by
Απάντηση
(B)
friction
38
Which of the following factors does not affect the e.m.f of a primary cell? Its
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(A)
size
39

Two magnets are used to magnetize a soft iron bar PQ as illustrated in the diagram given. The correct polarity at P and Q respectively
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(B)
N and N
40
In storing magnets, keepers are used to
Απάντηση
(A)
reduced self-demagnetization
41
A 10\(\mu\)C charge moves with a velocity of 1.0 x 10⁵ ms^-1 at right angle to a uniform magnetic field of flux density 5.0 x 10^-4T. Calculate the force on the charge
Απάντηση
(B)
5.0 x 10^-4N
42
Which of the following statements is not correct about steel and soft iron?
Απάντηση
(A)
steel is more magnetized than soft iron
43
What determines the polarity at the ends of an electromagnet? The
Απάντηση
(D)
direction of current in the wire
44
How many beta particle(s) are emitted in the radioactive decay of \(^{198}_{79}Au \leftarrow ^{198}_{80}Hg\)?
Απάντηση
(A)
1
45
The phenomenon by which two light atomic nuclear combine to form a heavy nuclide with the release of energy is known as
Απάντηση
(B)
nuclear fusion