WAEC Past Questions and Answers - Page 3291

16,451.

Total internal reflection occurs in an optical prism when light rays

A.

travel from the prism into an optically denser medium

B.

are incident in the prism at an angle greater than the critical angle

C.

are incident normally in the prism

D.

travel from the prism to the air

Correct answer is B

No explanation has been provided for this answer.

16,452.

Visible balance is also known as

A.

Terms of trade

B.

Balance of payments

C.

Balance of trade

D.

Capital balance

Correct answer is C

The visible trade balance is that part of the balance of trade figures that refers to international trade in physical goods, but not trade in services. It is also known as balance of payment in the current account balance.

16,453.

A ray undergoes a minimum deviation at 40o when it is incident on equilateral triangular glass prism. Calculate the refractive index of the prism

A.

1.48

B.

1.50

C.

1.53

D.

1.67

Correct answer is C

n = \(\frac{\sin \frac{1}{2} (dm + A)}{\sin \frac{1}{2} A}\)

= \(\frac{\sin \frac{1}{2} (40 + 60)}{\sin \frac{1}{2} \times 60}\)

= 1.532

16,454.

The image formed by a convex mirror is always

A.

real, erect and diminished

B.

real, inverted and diminished

C.

virtual, inverted and diminished

D.

virtual, erect and diminished

Correct answer is D

No explanation has been provided for this answer.

16,455.

Which of the following problems arises where there are more than one technically possible methods of production

A.

Where to produce

B.

For whom to produce

C.

How to produce

D.

What to produce

Correct answer is C

The problem of how to produce refers to selection of techniques to be used for production of goods and services. By technique we mean labour or capital intensive techniques. That is knowing the input combination to be used.