NECO Physics Past Questions & Answers - Page 37

182.

The inability of the eye to focus near objects is known as

A.

astigmatism

B.

eye ring

C.

hypermetropia

D.

myopia

E.

presbyopia

Correct answer is C

No explanation has been provided for this answer.

183.

Which of the following motions will be produced by a pair of equal, opposite and non-collinear parallel forces acting on a body?

A.

Oscillatory

B.

Random

C.

Rotational

D.

Translational

E.

Vibratory

Correct answer is C

A couple consists of two equal and opposite forces acting at a separation, so that net force becomes zero. When a couple acts on a body it rotates the body but does not produce any translational motion. Hence, only rotational motion is produced.

184.

A narrow, uniform glass tube, closed at one end, constains air which is sealed by a thread of mercury. The tube is placed first horizontally and then vertically with the open end at the top. Which of the following statements is correct?

A.

The length of the entrapped air in the horizontal position is less than that in the vertical position

B.

The length of the entrapped air in the vertical position is less than that in the horizontal position

C.

The length of the mercury column becomes shorter in the horizontal position than in the vertical position

D.

The length of the mercury column becomes shorter in the vertical position than in the horizontal position

E.

The pressure of the entrapped air is atmospheric in both cases.

Correct answer is B

No explanation has been provided for this answer.

185.

The S.l unit of magnetic flux density is

A.

farad

B.

henry

C.

kgm-3

D.

tesla

E.

weber

Correct answer is D

No explanation has been provided for this answer.