JAMB Physics Past Questions & Answers - Page 95

471.

A ball is dropped from the top of a tower. Due to air resistance,it reaches terminal velocity. Which of the following statement(s) about its motion is/are correct? i. The acceleration of the ball is zero. ii. The net force on the ball is zero. iii. The velocity of the ball increases.

A.

i only

B.

i and ii only

C.

ii and iii only

D.

i, ii and iii

Correct answer is B

Terminal velocity refers to the constant speed that an object reaches as it falls through a liquid or gas.

Since the net force on the object is zero, the object has zero acceleration.

472.

The diagram given, represents the graph of stress against strain for an elastic wire. The point Q on the graph is the

A.

elastic limit

B.

breaking point

C.

yield point

D.

proportional limit

Correct answer is B

No explanation has been provided for this answer.

473.

A student measures the volume of a liquid using a measuring cylinder. What else needs to be measured by the student in order to determine the density of the liquid?

A.

depth of the liquid in the cylinder

B.

mass of the cylinder

C.

mass of the liquid

D.

temperature of the liquid

Correct answer is C

No explanation has been provided for this answer.

474.

The dimensions of momentum are

A.

MLT

B.

ML-1T-1

C.

MLT-1

D.

ML-1T

Correct answer is C

Momentum = kgms-1 = MLT-1

475.

\(^{226}_{88}Ra\) emits two alpha particles to produce polonium(po) nuclide. The correct formula for the nuclide?

A.

\(^{224}_{86}po\)

B.

\(^{222}_{86}po\)

C.

\(^{222}_{84}po\)

D.

\(^{218}_{84}po\)

Correct answer is D

No explanation has been provided for this answer.