Physics Past Questions and Answers

I. They should be identical
II. They should originate from the same source.
III. They should be coherent.
IV. They should be monochromatic.
from the statements above, the conditions for two waves to interfere are?

A I,II and III only
B I, III and IV only
C II, III and IV only
D I, II, III and IV

Question 17:

In a large telecommunications auditorium, perforated absorbent materials are used to line the ceiling so as to

A Increase the reverberation of sound in the hall
B Increase the amount of echo in the hall
C Reduce the hight of the ceiling from the floor
D Reduce the reverberation of sound in the hall

Question 18:

The phenomenon of light bending round an obstacle is?

A Diffraction
B Refraction
C Reflection
D Polarization

Question 19:

The instrument used by designers to obtain different color pattern is called?

A Periscop
B Sextant
C Episcope
D Kaleidoscope

Question 20:

A glass plate 0.9cm thick has a reflective index of 1.50. how long does it take for a pulse of light to pass through the plate?
[c = 3.0 x ⁸ ms^-1]

A 4.5 x 10^-11s
B 4.5 x 10^-10s
C 4 .5 x 10^-12 s
D 3.0 x 10^-10s