NECO Past Questions and Answers - Page 196

976.

Which of the following is/are longitudinal wave(s)?

I. Light waves from the sun
II. Sound waves in the air
III. Waves on a vibrating string

A.

I only

B.

II only

C.

I and II only

D.

I and III only

E.

II and III only

Correct answer is B

No explanation has been provided for this answer.

977.

A radio station broadcasts at a frequency of 400KHz. If the speed of the wave is 3.0 ×10-8 ms-1, calculate the wavelength of the radio wave.

A.

1.3 × 102m

B.

3.0 × 102m

C.

2.4 × 102m

D.

5.0 × 102m

E.

7.5 × 102m

Correct answer is E

No explanation has been provided for this answer.

978.

A box is pulled a distance s along a smooth horizontal floor by a force of magnitude F, inclined at an angle θ to the horizontal. The work done is

A.

Fs cos θ

B.

Fs cosec θ

C.

Fs sec θ

D.

Fs sin θ

E.

Fs tan θ

Correct answer is A

No explanation has been provided for this answer.

979.

Which of the following will reduce the frequency of oscillation of a simple pendulum?

A.

Decreasing the length of the string

B.

Increasing the amplitude of oscillation

C.

Increasing the length of the string

D.

Increasing the mass of the bob

E.

Reducing the mass of the bob.

Correct answer is C

No explanation has been provided for this answer.

980.

Which of the following statements is correct?

A.

Alpha particles have a large mass and high penetrating power

B.

Alpha particles have a small mass and a low penetrating power

C.

Beta partials have no mass and a high penetrating power

D.

Beta particles have a large mass and a low penetrating power

E.

Gamma rays have no mass and a high penetrating power

Correct answer is E

No explanation has been provided for this answer.