21o
22o
23o
24o
Correct answer is D
SinC = \(\frac{1}{n}\)V2
SinC = \(\frac{1}{2.42}\)
SinC =24o
Total eclipse of the sun occurs when the
earth is between the moon and the sun
sun is between the moon and the earth
moon is between the sun and the earth
ozone layer is threatened
Correct answer is C
No explanation has been provided for this answer.
The pitch of an acoustic device can be increased by
increasing the frequency
increasing the amplitude
decreasing the loudness
decreasing the intensity
Correct answer is A
No explanation has been provided for this answer.
The difference between sound waves and light waves is that sound waves
are transverse while light waves are longitudinal
require a medium to travel while light waves does not
can be diffracted but light waves cannot
cannot be reflected but light waves can
Correct answer is B
No explanation has been provided for this answer.
7500m
300m
75m
15m
Correct answer is B
\(\lambda\)1F1 = \(\lambda\)2F2
1500 x 200000 = 1000000 x \(\lambda\)2
\(\lambda\)2 = 300m