The diagram above shows the magnetic field around a bar magnet which has its N-pole pointing north. The neutral points in the field are likely to occur at
A1 and 2
B3 and 4
C5 and 6
D7 and 8
E9 and 10
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Question 12
waec1992
A pipe closed at one end is 1.0m long. The air in the pipe is set into vibration and a fundamental note of frequency 85Hz is produced. Calculate the velocity of sound in the air. (Neglect end correction).
A340.0ms-1
B33Oms-1
C170ms-1
D85.0ms-1
E42.5ms-1
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Question 13
waec1992
Which of the following statements is not true?
AMusical notes consist of the combination of sounds of regular frequency
BThe combination of overtones produced by an instrument determines the quality of the sound
Cthe loudness of sound is determined by its frequency
Dthe pitch of a note depends on the frequency of vibration of the source
ENoise can be produced by a combination of sounds of irregular frequency
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Question 14
waec1992
Which of the following waves are longitudinal waves? l. Ripples on the surface of water II. Waves produced by a tuning fork vibrating in air III. Light waves
IV. Waves produced by a flute
AI and II only
BI and III only
CII and III only
DII and IV only
EIII and IV only
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Question 15
waec1992
How far from a cliff should a boy stand in order to hear the echo of his clap 0.9s later? (Speed of sound in air = 330 ms-1)
A36.67m
B74.25m
C148.50m
D297.00
E366.67m
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Question 16
waec1992
Which of the following radiations have the highest frequency?
ARadio waves
BLight waves
CX-rays
Dinfra-red rays
EUltraviolet rays
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Question 17
waec1992
The diagram above shows a waveform in which energy is transferred from A to B in a time of 2.5 x 10-3s. Calculate the frequency of the wave
A2.0 x 103Hz
B1.0 x 103Hz
C4.0 x 10-2Hz
D1.0 x 10-3Hz
E5.0 x 104Hz.
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Question 18
waec1992
The change of the direction of a wavefront as a result of a change in the velocity of the wave in another medium is called
Arefraction
Breflection
Cdiffraction
Dpolarization
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Question 19
waec1992
The angle of deviation of light of various colours passing through a glass prism decreases in the order of
Ablue orange and red
Bred, blue and orange
Cblue, red and orange
Dred, orange and blue
Eorange, blue and red
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Question 20
waec1992
Which of the following is used for controlling the amount of light entering the eye?
ACornea
BPupil
CIris
DOptic nerve
ECiliary muscle
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Question 21
waec1992
When an astronomical telescope is in normal adjustment, the focal length of the objective lens is 50cm and that of the eyepiece is 2.5om. What is the distance between the lenses?
A20.0cm
B47.5cm
C50.0cm
D52.5cm
E125.0cm.
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Question 22
waec1992
The eye defect illustrated in the diagram above can be corrected by a
Aconvex mirror
Bconcave mirror
Cdiverging lens
Dconverging lens
Epiano-converging lens
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Question 23
waec1992
A real image of an object fom1ed by a converging lens of focal length 15cm is three times the size of the object. What is the distance of the object from the lens?
A30cm
B25cm
C20cm
D15cm
E10cm
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Question 24
waec1992
As an object is moved close to the focus of a converging lens from infinity its image I. moves closer to the lens II. moves away from the lens. III. Remains the same size. IV becomes smaller. Which of the statements above is/are correct?
AIII and IV only
BI and III only
CIV only
DIII only
EII only
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Question 25
waec1992
The image of a pin formed by a diverging lens of focal length 10cm is 5cm from the lens. Calculate the distance of the pin from the lens
A-3.3cm
B3.3cm
C10.0cm
D15.0cm
E20.0cm
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Question 26
waec1992
In an experiment to measure1 the focal length f of a converging lens object distances u and corresponding image distance were measured and 1/u plotted against 1/v to obtain the graph illustrated. How would f be determined from this graph?
Af= the slope of the graph
Bf= the intercept on the 1/u axis
Cf =the intercept on the 1/v axis
Df = reciprocal of the slope
Ef = reciprocal of the intercept on either axes
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Question 27
waec1992
Which of the following statements is not correct for a light ray passing through a rectangular glass block which is surrounded by air? It
Asuffers a displacement at the point of emergence
Bemerges parallel to the incident ray
Cis partly reflected at the point of incidence
Dis deviated at the point of emergence
Eis reflected in the block
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Question 28
waec1992
Images formed by a convex mirror are always
Ainverted, real and diminished
Binverted, virtual and diminished
Cerect, virtual and diminished
Derect, real and magnified
Eerect, virtual and magnified
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Question 29
waec1992
A ray of light strikes a plane mirror at an angle of incidence i. Determine in terms of i the angle of deviation of the ray after reflection from the mirror.
Ai
B2i
C90o-i
D90o+ i
E180o - 2i
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Question 30
waec1992
A metal of mass 1.5 kg was heated from 27oC to 47oC in 4 minutes by a boiling ring of 75 W rating. Calculate the specific heat capacity of the metal, (Neglect heat losses to the surrounding)
