Jamb Physics 1985 Past Questions and Answers

Question 31:

• JAMB 1985

A convex mirror is used as a driving mirror because i. its image is erect. ii. it has a large field of view. iii. it has a long focal length. Identify the CORRECT statement(s)

A. I andiii only
B. I and ii only
C. Ii and iii only
D. I, ii, and iii only
E. I only

Question 32:

• JAMB 1985

Two rays of light from a point below the surface of water are equally inclined to each other at 60^o in water. What is the angle between the rays when they emerge into air? (Take the refractive index of water to be \(\frac{4}{3}\))

A. 41.8^o
B. 44.1^o
C. 60.0^o
D. 83.6^o
E. 120.0^o

Question 33:

• JAMB 1985

A narrow beam of white light can be split up into different colours by a glass prism. The correct explanation is that

A. White light is an electromagnetic wave
B. The prism has all the colours of the white light
C. White light has undergone total internal reflection in the prism
D. Different colours of white light travel with different speeds in glass
E. White ligth consist of yellow, green and red colours

Question 34:

• JAMB 1985

A charge of one coulomb liberates 0.0033g of copper in an electrolytic process. How long will it take a current of 2A to librate 1.98g of copper in such a process?

A. 5 mins
B. 30 mins
C. 50 mins
D. 60 mins
E. 120 mins

Question 35:

• JAMB 1985

If the distance between two stationary charged particle is doubled, the magnitude of the electro-static force between them will be

A. Doubled
B. Halved
C. A quarter of its former value
D. Unchanged
E. Four times the original value