JAMB Physics Past Questions & Answers - Page 296

1,476.

Which of the following are produced after a nuclear fusion process?

i. one heavy nucleus.
ii. neutrons-1.
iii. protons.
iv. Energy.

A.

i and ii

B.

i and iv

C.

ii and iii

D.

ii and iv

Correct answer is B

No explanation has been provided for this answer.

1,477.

Natural radioactivity is the random spontaneous disintegration of the nuclei of heavy isotopes of certain elements with the emission of

A.

\(\alpha\), X, and \( \beta\)

B.

\(\alpha\), \(\beta\) and \(\gamma\)-rays

C.

X, \(\alpha\), \(\gamma\)-ray

D.

\(\alpha\), \( \beta\) and X-rays

Correct answer is B

No explanation has been provided for this answer.

1,479.

Determine the inductive reactance when a 30.0mH inductor with a negligible resistance is connected to a 1.3 x 103Hz oscillator.

A.

39.0\(\Omega\)

B.

122.5\(\Omega\)

C.

245.0\(\Omega\)

D.

39000.0\(\Omega\)

Correct answer is C

XL = 2\(\pi\)FL

= 2 x 3.142 x 30 x 10-3 x 1.3 x 103

= 245\(\Omega\)

1,480.

The primary aim in high tension transmission is to

A.

minimize electrical energy losses due to heat production

B.

increase the rate of energy transfer by using high voltage

C.

increase the current in the wire

D.

generate electricity at high current and low voltage

Correct answer is A

No explanation has been provided for this answer.