WAEC Past Questions and Answers - Page 3273

16,361.

In a situation where the finished product of an industry is fragile, bulky and perishable, such an industry should be located close to its

A.

Raw materials

B.

Market

C.

Labour supply

D.

Power supply

Correct answer is B

An industry whose products are bulky, perishables and fragile should be located close to the market. This is to make sure such goods are sold early and fast to avoid the goods getting bad or destroyed while on transit.

16,362.

An object is placed 10cm from a converging lens of foal length 15cm. Calculate the magnification of the image formed

A.

3.0

B.

1.5

C.

0.6

D.

0.3

Correct answer is C

* produces a virtual image when object distance(u) is less than its focal length(f).

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

\(\frac{1}{v} = \frac{1}{f} + \frac{1}{u}\)

\(\frac{1}{15} + \frac{1}{10} = \frac{2 + 3}{30}\)

\(\frac{1}{v} = \frac{5}{30}\)

v = 6.0 cm 

but m = \(\frac{v}{u} = \frac{6}{10} = 0.6\)

Note that the negative sign only shows the placement of the image. It has no effect on the magnification basically.

16,363.

One of the problems facing industrial development in West African countries is

A.

Inadequate large market

B.

Inadequate infrastructure

C.

Inadequate supply of labour

D.

Unavailability of natural resources

Correct answer is B

Developing countries like those in west Africa frequently lack adequate physical and social infrastructure of all kinds and their substantial improvement is essential for rapid economic development. This has been a major setback on industrial development in the area.

16,365.

A ray of light passes from air to water to glass to air. Given that the refractive index for light passing from air to water is \(\frac{4}{3}\) and air to glass is \(\frac{3}{2}\), calculate the refractive index of glass relative to water

A.

0.50

B.

0.67

C.

0.75

D.

1.13

Correct answer is D

\(_{g} \eta _{w} = \frac{ _g \eta _a}{ _a \eta _w}\)

= \(\frac{3}{2} \times \frac{1}{\frac{4}{3}}\)

= \(\frac{3}{2} \times \frac{3}{4}\)

= \(\frac{9}{8}\)

= 1.125

= 1.13 (to 2 d.p)