WAEC Past Questions and Answers - Page 3577

17,881.

The responsiveness of demand to a change in income is the measurement of

A.

Foreign exchange rate

B.

Cross elasticity of demand

C.

Income elasticity of demand

D.

Price index elasticity

Correct answer is C

No explanation has been provided for this answer.

17,882.

If the frequency of the tuning fork at resonance is 256Hz, calculate the frequency of vibration of the wire when the tension in the wire is increased to 196N

A.

130.6Hz

B.

182.9Hz

C.

358.4Hz

D.

501.8Hz

Correct answer is C

\(\frac{f}{256} = \sqrt{\frac{196}{100}}\)

f = \(\sqrt{\frac{256^2 \times 196}{100}}\)

= 356.4Hz

17,884.

Which of the following statements about sound is correct?

A.

when sound travels from air to a denser medium, it is refracted away from the normal at the point of incidence

B.

sound travels faster in air than in water

C.

the wavelength of sound changes when it travels from to water

D.

the frequency of it travels from air to water

Correct answer is C

No explanation has been provided for this answer.

17,885.

Dispersion of white light by a glass prism occurs because

A.

white light consist of a mixture of seven different colour

B.

the refractive index of glass is different from each constituent colour of white light

C.

the speed of each colour of light in the glass is proportional to the refractive index of glass for each colour

D.

the speed of each colour of light in the glass is proportional to the angle of refraction in he prism

Correct answer is D

No explanation has been provided for this answer.