Question 536:

• JAMB 1989

A mass of gas at 7^oC and 70cm of mercury has a volume of 1200cm³. Determine its volume at 27^oC and pressure of 75cm of mercury.

A. 1200cm³
B. 1378cm³
C. 4320cm³
D. 4629cm³

Question 537:

• JAMB 1989

An electric heater is used to melt a block of ice of mass 1.5kg. If the heater is powered by a 12V battery and a current of 20A flows through the coil, calculate the time taken to melt the block of ice at 0^oC. [specific latent heat of fusion of ice = 336 x 10³Jkg^-1]

A. 76.0min
B. 35.0min
C. 21.0min
D. 2.9min

Question 538:

• JAMB 1989

From the kinetic theory of gases, temperature is a

A. Form of energy and is proportional to the total kinetic energy of the molecules
B. Form of energy and is proportional to the average kinetic energy of the molecules
C. Physical property and is proportional to the total kinetic energy of the molecules
D. Physical property and is proportional to the average kinetic energy of the molecules

Question 539:

• JAMB 1989

A vibrator of frequency 60Hz is used in generating transverse stationary waves in a long thin wire, If the average distance between successive nodes on the wire is 45cm, find the speed of the transverse waves in the wire.

A. 27ms^-1
B. 54ms^-1
C. 90ms^-1
D. 108ms^-1

Question 540:

• JAMB 1989

When the tension in a sonometer wire is doubled, the ratio of the new frequency to the initial frequency is

A. \(\frac{1}{\sqrt2}\)
B. \(\frac{1}{2}\)
C. \(\sqrt2\)
D. 2