Question 61:

• JAMB 1979

Two closed vessels contain equal volumes of boiling water and are identical except that one is blackened on the outside while the other is polished. Which of the following is correct?

A. The polished vessel will cool faster because a polished surface is a good radiator
B. The polished vessel will cool faster because it will absorbe less heat from the room
C. The black vessel will cool faster because it is a better conductor of heat
D. The polished vesselwill cool faster because it reflects heat better
E. The black vessel will cool faster because a black surface radiates heat faster than a polished one

Question 62:

• JAMB 1979

The temperature at which the water vapour present in the air saturates the air and begins to condense is known as

A. Boiling point
B. Melting point
C. Triple point
D. Dew point
E. Critical temperature

Question 63:

• JAMB 1979

Which of the following types of waves cannot travel through a vacuum?

A. Sound waves
B. Light waves
C. Infra-red waves
D. X-radiation
E. Redio waves

Question 64:

• JAMB 1979

If in a simple pendulum experiment the length of the inextensible string is increased by a factor of four, its period is increased by a factor of

A. 4
B. \(\frac{\pi}{2}\)
C. \(\frac{1}{4}\)
D. 2\(\pi\)
E. 2

Question 65:

• JAMB 1979

In what range of temperature is the expansion of water anomalous?

A. +208^oC to +212^oC
B. -80^oC + -76^oC
C. -4^oC to 0^oC
D. +96^oC to +100^oC
E. 0^oC to +4^oC