WAEC Physics Past Questions & Answers - Page 136

677.

In a nuclear reactor, chain reactions result from the release of

A.

electrons

B.

photons

C.

neutrons

D.

protons

Correct answer is C

No explanation has been provided for this answer.

678.

The number of protons in an element increased by one after a radioactive decay. The element must have decayed by emitting

A.

a beta particle

B.

an alpha particle

C.

a gamma ray

D.

a neutron

Correct answer is A

No explanation has been provided for this answer.

679.

If a gas is excited by high voltage to produce a discharge and the light is examined in a spectrometer

A.

an explosion is observed

B.

the rainbow colours are seen

C.

an emission spectrum is observed

D.

dark lines are observed

Correct answer is C

No explanation has been provided for this answer.

680.

Which of the following electromagnetic wave can be detected by its heating effect?

A.

ultraviolet radiation

B.

x-rays

C.

gamma rays

D.

infrared radiation

Correct answer is D

No explanation has been provided for this answer.