Light Energy - Jamb Physics Past Questions and Answers

Question 6:

• JAMB 1993

Radio waves emitted from an antenna are picked up by a radar after reflection from an aircraft in 4 x 10^-3S. How far is the aircraft from the antenna? [c = 3 x 10⁸ms^-1 ]

A. 6.0 x 10²ms^-1
B. 1.2 x 10³km
C. 3.0 x 10³km
D. 6.0 x 10 ⁵km

Question 7:

• JAMB 1995

Total eclipse of the sun occurs when the

A. Earth is between the moon and the sun
B. Sun is between the moon and the earth
C. Moon is between the sun and the earth
D. Ozone layer is threatened

Question 8:

• JAMB 1997

Light of velocity 3 x 10⁸ms^-1 is incident on a material of reflective of index n. If the velocity of light is reduced to 2.4 x 10⁸ms^-1 in the material, what is n?

A. 2.33
B. 2.25
C. 1.33
D. 1.25

Question 9:

• JAMB 1997

When the sun, moon and the earth are as shown in the diagram above an observer standing in X is in

A. Penumbra and sees a partial eclipse
B. Penumbra and sees a total eclipse
C. Umbra and sees a partial eclipse
D. Umbra and sees a total eclipse

Question 10:

• JAMB 2003

The operation of an optical fibre is based on the principal of

A. Dispersion of light
B. Interference of light
C. Refraction of light
D. Polarization of light