WAEC Past Questions and Answers - Page 3227

16,131.

The general gas law can be written as

A.

PV ÷ T = a constant

B.

PV = a constant

C.

v/t = a constant

D.

p/T = a constant

Correct answer is A

Formula for general gas law

V × 1/T × P

N [(PV) ÷ T] = K is constant

There is an explanation video available below.

16,132.

In an elastic collision

I. Energy is conserved
II. Energy is decreased
III. Energy is increased
IV. Linear momentum conserved

A.

I only

B.

I and IV only

C.

II only

D.

III only

Correct answer is B

In an inelastic collision, linear momentum is conserved and energy is decreased

Momentum and kinetic energy are conserved in elastic collision

There is an explanation video available below.

16,133.

A stroboscope can be used to make the wave appear ………….

A.

Stationary

B.

In motion

C.

Dipper

D.

Ripple

Correct answer is A

Stroboscope is a scientific instrument used to make a wave appears stationary when used

There is an explanation video available below.

16,134.

What is the inductance (L) of an inductor whose reactance is 1Ω at 50/ π hertz (H)?

A.

100 H

B.

0.01H

C.

10H

D.

1H

Correct answer is B

XL = WL = 2πFL (w = 2πf)

XL = reactance inductor (S.I unit Ω)

L = inductance (L) in Henry

XL = 1Ω, f = 50/π, L = ?

1 = 2× π × 50/π × L

1 = 100L

i.e. 100L = 1

L = 1/100

0.01H

∴ Inductance (L) of a inductor = 0.01H

There is an explanation video available below.

16,135.

The direction of the path taken by light is called

A.

Locus

B.

Lines

C.

Ray

D.

Beam

Correct answer is C

Ray – a beam of light or radiation

There is an explanation video available below.