WAEC Past Questions and Answers - Page 3290

16,446.

An object is placed 20.0cm in front of a converging lens of focal length 15.0cm. Calculate its image distance

A.

1.3cm

B.

8.6cm

C.

35.0cm

D.

60.0cm

Correct answer is D

\(\frac{1}{v} = \frac{1}{f} - \frac{1}{U}\)

\(\frac{1}{15} - \frac{1}{20} = 60cm\)

16,447.

The speed of light in a certain medium is V while its speed in a vacuum is C. The absolute refractive index of the medium is

A.

C + V

B.

\(\frac{C}{V}\)

C.

\(\frac{V}{C}\)

D.

C - V

Correct answer is B

No explanation has been provided for this answer.

16,448.

A condition for consumer utility maximization is

A.

Equality of the ratio of marginal utilities and the ratio of prices

B.

Equality of the ratio of average utilities and the ratio of prices

C.

Equality of the marginal utility to total utility ratio for both commodities

D.

Total utility and marginal utility must be zero

Correct answer is A

In Utility Maximization, the consumers decide to spend their money so that the amount spent on each product purchased yields the same amount of extra marginal utility. The consumer would maximize its utility when marginal utility equals the price paid for the commodities.

16,449.

If a 6% decrease in price results in more than 6% decrease in quantity supplied, supply can be regarded as

A.

Elastic

B.

Unitary elastic

C.

Perfectly inelastic

D.

Perfectly elastic

Correct answer is A

The law of supply states that there is a direct relationship between the quantity supplied and the price of a commodity. If a change in price causes a change in the quantity supplied, this means the supply is elastic.

16,450.

A shift in the demand curve indicates

A.

Exceptional demand

B.

Change in demand

C.

Change in quantity demanded

D.

Elasticity of demand

Correct answer is B

A shift in the demand curve means that other determinants of demand other than price causes demand to change. They include changes in tastes, population, income, prices of substitute or complementary goods, and expectations about future conditions and prices. This is usually an indication of a change in demand.

A change in demand describes a shift in consumer desire to purchase a particular good or service, irrespective of the price difference.