Question 366:

• JAMB 1985

A 45^o triangular glass prism can be used as a reflector of light because

A. A refraction never takes place in such a prism
B. The angle of reflection equals the angle of incidence
C. The refractive index of glass is less than 1
D. It is transparent
E. The critival angle angle for glass is less than 45^o

Question 367:

• 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 368:

• 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 369:

• 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 370:

• 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