WAEC Physics Past Questions & Answers - Page 240

1,196.

Which of the following is not a safety precaution in a nuclear station?

A.

Radioactive materials are stored in glass casings

B.

Radioactive materials are handled with remote-controlled tongs

C.

Technicians in nuclear stations wear radio-sensitive badges which are checked regularly.

D.

Technicians in nuclear stations wear radio-sensitive badges which are checked regularly.

Correct answer is B

No explanation has been provided for this answer.

1,197.

Which of the following are the essential parts of an atomic bomb?

A.

Uranium and neutrons

B.

Radium and polonium

C.

Nitrogen and neutrons

D.

ranium and α - particles.

Correct answer is A

No explanation has been provided for this answer.

1,199.

The half-life of a radioactive element is 5 Calculate its decay constant

A.

0.113s-1

B.

0.436 s-1

C.

0.139 s-1

D.

0.193 s-1.

Correct answer is C

No explanation has been provided for this answer.

1,200.

A metal has work function of 4.375 eV Calculate its threshold frequency. (h = 6.6 x 10-34Js; 1eV = 1.6 x 10-19J)

A.

2.01 X 1015Hz

B.

1.06x1015Hz

C.

6.30 x 1014Hz

D.

1.60 x 1014Hz

Correct answer is B

No explanation has been provided for this answer.