Physics 1992 Waec Past Questions and Answers

Question 36 :

• WAEC 1992

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)

A. 36.67m
B. 74.25m
C. 148.50m
D. 297.00
E. 366.67m

Question 37 :

• WAEC 1992

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

A. I and II only
B. I and III only
C. II and III only
D. II and IV only
E. III and IV only

Question 38 :

• WAEC 1992

Which of the following statements is not true?

A. Musical notes consist of the combination of sounds of regular frequency
B. The combination of overtones produced by an instrument determines the quality of the sound
C. The loudness of sound is determined by its frequency
D. The pitch of a note depends on the frequency of vibration of the source
E. Noise can be produced by a combination of sounds of irregular frequency

Question 39 :

• WAEC 1992

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).

A. 340.0ms^-1
B. 33Oms^-1
C. 170ms^-1
D. 85.0ms^-1
E. 42.5ms^-1

Question 40 :

• WAEC 1992

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

A. 1 and 2
B. 3 and 4
C. 5 and 6
D. 7 and 8
E. 9 and 10