WAEC Physics Past Questions & Answers - Page 219

1,091.

The lower and upper fixed points of a mecury-in-glass thermometer are marked Y and 180mm respectively. On a particular the mecury meniscus in the thermometer rises to 45mm. If the corresponding reading on a scale is 10o, calculate the value of Y.

A.

4mm

B.

18mm

C.

30mm

D.

135mm

E.

450mm

Correct answer is C

by interpolation,

\(\frac{100 - 0}{10- 0} = \frac{180 - y}{45 - y}\)

\(\frac{100}{10} = \frac{180 -y}{45 - y }\)

450 - 10y = 180 - y 

- 9y = - 270 

y = 30mm

 

1,092.

An object is heated from 30°C to 57°C. The increase in its temperature on the Kelvin scale is

A.

17k

B.

27k

C.

81k

D.

246k

E.

300k

Correct answer is B

30°C + 273 = 303K

57°C + 273 = 330K

∆T = 330K - 303K

→ 27K

1,093.

The earth is not a perfect sphere because its equatorial axis is longer than the polar axis. where on the earth's surface would an object have its greatest weight?

A.

half way between the equator and the north pole

B.

near the equator

C.

half way between the equator and the south pole

D.

at either pole

E.

at the equator

Correct answer is C

No explanation has been provided for this answer.

1,094.
1,095.

If the box is pulled from P to Q, which of the following expresses the velocity ratio of the inclined plane?

A.

PR/PQ

B.

OR/PQ

C.

OR/PR

D.

PQ/PR

E.

PQ/QR

Correct answer is E

No explanation has been provided for this answer.