Question 501:

• JAMB 1988

The speed of sound in air at sea-level is 340ms^-1 while that of light is 300 000kms^-1. How far (to the nearest meter) from the center of a thunderstorm is an observer who hears a thunder 2s after a lightening flash?

A. 170ms^-1
B. 340ms^-1
C. 600ms^-1
D. 680ms^-1

Question 502:

• JAMB 1988

A slight loading of a tuning fork has the effect of

A. Decreasing its amplitude
B. Increasing its amplitude
C. Decreasing its frequency
D. Increasing its frequency

Question 503:

• JAMB 1988

Two strings of the same length and under the same tension gives notes of frequencies in the ratio 4 : 1. The masses of the strings are in the corresponding ratio of

A. 2 : 1
B. 1 : 2
C. 1 : 4
D. 1 : 16

Question 504:

• JAMB 1988

To obtain a magnification of 2.5, how far should an object be placed from the pole of a thin converging lens of focal length 10.20m?

A. 0.13m
B. 0.25m
C. 0.28m
D. 0.50m

Question 505:

• JAMB 1988

An object is placed 10cm in front of a concave mirror of focal length 15cm. What is the position and nature of the image formed?

A. 30cm and virtual
B. 6cm and real
C. 6cm and virtual
D. 30cm and real