1993 - WAEC Physics Past Questions and Answers - page 3
21
An object is placed between two mirrors which are inclined at an angle of 120° and facing each other. Determine the number of images observed in the two mirrors
A
1
B
2
C
3
D
4
correct option: b
Users' Answers & Comments22
In a ripple tank experiment, a vibrating plate is used to generate ripples in the water. If the distance between two successive troughs is 3.5 cm and the wave travels a distance of 31.5 cm in 1.5 s, calculate the frequency of the vibrator
A
3.0Hz
B
6.0Hz
C
12.0Hz
D
27.0Hz
23
Which of the following have the longest wavelengths?
A
Infra-red rays
B
Gamma rays
C
X-rays
D
Ultra-violet rays
correct option: e
Users' Answers & Comments24
A man stands in front of a tall wall and produces a sound. If he receives the echo of the sound two seconds later, calculate his distance from the wall. (The speed of sound in air is 330ms-1)
A
600m
B
400m
C
330m
D
328m
25
Which of the following is correct about light and sound waves?
A
Both of them are associated with energy transfer
B
Both of them need material media for propagation
C
they are both longitudinal waves
D
their velocities in air are equal
correct option: a
Users' Answers & Comments26
The quality of a note produced by a vibrating string is determined by the
A
pitch of the note
B
tension of the string
C
material of the string
D
presence of overtones
correct option: a
Users' Answers & Comments27
Which of the following is a percussion instrument?
A
Flute
B
Organ
C
Bell
D
Piano
correct option: c
Users' Answers & Comments28
A short chain is usually attached to the back of a petrol tanker and trailing behind it so that the
A
petrol tanker is balanced on the road
B
heat generated by friction in the engine can be conducted to the earth
C
charges generated by friction in the tanker are conducted to the earth
D
tanker can move slowly as the chain touches the road surface
correct option: c
Big vehicles gets charged because of friction between them and the air rushing past them.This is the reason tankers often have a metal chain dragging along the ground so that charge produced leaks to the ground through chain.
29
Which of the following indicates the correct sequence of steps taken in charging a gold-leaf electroscope by induction? l. Removing the ebonite rod ll. Bringing a negatively charged ebonite rod close to the cap III. Earthing the cap IV. Disconnecting the earthing
A
III, II, I and IV
B
II, I, III and IV
C
III, IV II and I
D
II, III, IV and I
correct option: d
Users' Answers & Comments30
Which of the following instruments can be used to compare the relative magnitude of similar charges on two given bodies?
A
Electrophorus
B
Ebonite rod
C
Proof plane
D
Gold-leaf electroscope
correct option: d
Users' Answers & Comments