Waec Physics 1995 Past Questions and Answers

Question 16:

• WAEC 1995

An air bubble of volume 2 cm\(^3\) is formed 20m under water. What will be its volume when it rises to just below the surface of the water if the atmospheric pressure is equivalent to a height of 10m of water?

A. 6cm³
B. 4cm³
C. 3cm³
D. 2cm³
E. 1cm³

Question 17:

• WAEC 1995

The pressure of a given mass of gas changes from 200 Nm² to 100 N m², while its temperature drops from 127^oC to - 73^oC. Calculate the radio of the final volume of the gas to its initial volume.

A. 2.4:1
B. 2.0:1
C. 1.2:1
D. 1.0:1
E. 1.0:2

Question 18:

• WAEC 1995

The temperature of glass vessel containing 100cm3 of mercury is raised from 10^oC to 100^oC. Calculate the apparent cubic expansion of the mercury. (Real cubic expansivity of mercury = 1.82 x 10^-4K^-1) (Cubic expansivity of glass = 2.4 x 10^-5K^-1)

A. 0.52cm³
B. 1.42cm³
C. 1.87cm³
D. 5.22cm³
E. 14.22cm³

Question 19:

• WAEC 1995

An iron rod of mass 2kg and at a temperature of 280^oC is dropped into some quantity of water initially at a temperature of 30^oC. lf the temperature of the mixture is 70^oC, calculate the mass of the water. (Neglect heat losses to the surroundings). Specific heat capacity of iron = 460 J kg^[/sup]K[sup]) (Specific heat capacity of water = 4200 Jkg ^[/sup]K[sup])

A. 0.58kg
B. 0.77kg
C. 1.15kg
D. 1.50kg
E. 2.04kg

Question 20:

• WAEC 1995

How much heat is required to convert 20 g of ice at 0^oC to water at the same temperature? (Specific latent heat of ice = 336 J g^-1)

A. 1.35 x 10³J
B. 5.38 x 10³J
C. 6.72 x 10³J
D. 7.06 x 10³J
E. 8.06 x 10³J