In an RLC series circuit at resonance, the voltages across the resistor and the inductor are 30 V and 40 V respectively. Determine the voltage across the capacitor.

• A. 50V
• B. 30V
• C. 70V
• D. 40V

A very sensitive spring balance was used to determine the weight of an object at the north pole. When the same spring balance was used to measure the weight of the same object at the equator, it was found to reduce. The explanation for this observation is that

• A. it is very hot at the equator
• B. the spring balance has expanded
• C. the acceleration of free fall due to gravity varies with location
• D. the mass of the body is reduced

(a) List two factors each that affect heat loss by:

(i) radiation;

(ii) convection.

(b) State two factors that determine the quantity of heat in a body.

(c) Explain the statement: The vecilic latent heat of vaporization of mercury is 2.72 x 10\(^5\) Jkg\(^{-1}\).

(d)A jug of heat capacity 250 Jkg\(^{-1}\) contains water at 28°C. An electric heater of resistance 35\(\Omega\) connected to a 220 V source is used to raise the temperature of the water until it boils at 100°C in 4 minutes. After. another 5 minutes, 300 g of water has evaporated. Assuming no heat is lost to the surroundings, calculate the:

(i) mass of water in the jug before heating;

(ii) specific latent heat of vaporization of steam. [Specific heat capacity of water = 4200 kg\(^{-1}\)K\(^{-1}\)]

What is the escape velocity of a body on the surface of the earth of radius R if the gravitational constant is G and the mass of the earth is M? (Neglect energy losses to the surroundings)

• A. 2GR
• B. 2G/R
• C. 2GR²
• D. 2GM/R

Which of the following statements about pressure is not correct? pressure

• A. increases with an increase in surface area
• B. decreases with an increase in surface area
• C. increases with a decrease in surface area
• D. increases with an increase in the applied force

In which of the following states of matter do the molecules vibrate about their mean positions?

• A. liquids only
• B. solids only
• C. liquids and gasses only
• D. solids, liquids and gases

To obtain a virtual, erect and magnified image from a thin converging lens, an object must be placed

• A. between the focus and the lens
• B. at the focus
• C. between the focal length and twice the focal length
• D. beyond twice the focal length

A body moving with uniform acceleration has two points(5, 15) and (20, 60) on the velocity-times graph of its motion. Calculate

• A. 0.25ms^-2
• B. 3.00ms^-2
• C. 4.00ms^-2
• D. 9.00ms^-2

Which of the following waves is both transverse and mechanical?

• A. Water waves
• B. Radio waves
• C. Sound waves
• D. X-rays

In the formation of sea breeze, wind blows from?

• A. sky to land
• B. sea to sky
• C. land to sea
• D. sea to land