The bob of a simple pendulum takes 8.0s to complete 10 oscillations. Determine the frequency of oscillation of the bob.

• A. 0.125Hz
• B. 1.25Hz
• C. 7.50Hz
• D. 8.00Hz

Which electrical device is illustrated above?

• A. a.c. generator
• B. a.c. motor
• C. d.c. generator
• D. d.c. motor

The diagram below illustrates the mercury-in-glass thermometer used for determining the temperature of a room. Use the data on it to determine the room temperature.

• A. 3.3°C
• B. 7.0°C
• C. 13°C
• D. 30.0°C

Two plane mirrors are inclined to each other such that an object placed between them has 11 images. Determine the angle of inclination

• A. 30°
• B. 45°
• C. 60°
• D. 90°

A black body radiates maximum energy when its surface temperature T and the corresponding wavelength \(\lambda\)max are related by the equation \(\lambda\)max T = constant. Given the values of the constant and surface temperature as 2.9 x 10\(^{-3}\) mK and 57°C respectively; Calculate the frequency of the energy radiated.

Frequency is measured in

• A. meter per second
• B. seconds
• C. hertz
• D. farad

State three materials used for making optical fibres.

Rainbow formation is a natural phenomenon illustrating that white light

• A. splits into three components after rainfall
• B. is dispersed by glass prisms
• C. splits into its constituent colours before rainfall
• D. is dispersed into its constituent colours after rainfall

In which of the following activities is an induction coil not useful?

• A. Investigation of high voltages
• B. Study of electric discharge
• C. Operation of X-ray tubes
• D. A.C. power transmission

According to Newton's law of cooling, the heat energy lost per unit area of a body depends on the

I. Surface area

II. Nature of the surface

III. Temperature of the surface

IV. Excess temperature over the surroundings

• A. I and II only
• B. II and IV only
• C. I,II and III
• D. I, II and IV