WAEC Physics Past Questions & Answers - Page 188

936.

A slinky spring fixed at one end is placed horizontally on a table. The free end is displaced parallel to the table and then released. The resultimg wavelength is

A.

transverse

B.

longitudinal

C.

stationary

D.

electromagnetic

Correct answer is B

No explanation has been provided for this answer.

937.

What type of motion does the skin of a 'talking' drum perform when it is struck with a drum stick?

A.

Random

B.

Rational

C.

Translational

D.

vibratory

Correct answer is D

No explanation has been provided for this answer.

939.

Water of mass 120g at 50°C is added to 200g of water at 10°C and the mixture is well stirred. Calculate the temperature of the mixture. [Neglect heat losses to the surrounding]

A.

60oC

B.

40oC

C.

25oC

D.

10oC

Correct answer is C

120 x 4.2(50 - \(\theta\)) = 200 x 4.2(\(\theta\) - 10)

\(\theta = \frac{33600}{1344} = 25^oC\)

940.

The ice and steam points of a certain thermometer are -20° and 100° respectively. Calculate the Celsius temperature corresponding to 70° on the thermometer

A.

84.0o

B.

75.0o

C.

64.0o

D.

58.0o

Correct answer is B

\(\frac{70 -(- 20)}{100 -(-20)} = \frac{\theta - 0}{100 - 0}\)

\(\theta = \frac{90 \times 100}{120} = 75^oC\)