A submarine is observed to rise from a real depth off 80 m to 60 m in water. calculate the change in apparent depth.

[Refraction index of water 4/3]

• A) 45 m
• B) 80 m
• C) 15 m
• D) 60 m

Which of the following sources of energy is/are exhausible? i. Solar ii. Fossil fuels iii. Tidal power

• A. i, ii and iii
• B. i and ii only
• C. i and iii only
• D. ii and iii only

An object is placed 10cm from a converging lens of foal length 15cm. Calculate the magnification of the image formed

• A. 3.0
• B. 1.5
• C. 0.6
• D. 0.3

Which of the following values on the absolute scale of temperature is the ice point?

• A. 0K
• B. 32K
• C. 100K
• D. 273k

The slope of the straight line displacement-time graph indicates?

• A. distance traveled
• B. uniform velocity
• C. uniform acceleration
• D. uniform speed

The saturated vapour pressure of a liquid increases as the

• A. volume of the liquid increases
• B. volume of the liquid decreases
• C. temperature of the liquid increases
• D. temperature of the liquid decreases

The radiator of a motor car is cooled by

• A. radiation
• B. conduction
• C. convection
• D. radiation and conduction

The diagram below represents the graph of the force F applied in stretching a spiral spring against the corresponding extension (X). The force constant of the spring is

• A) 20 N/m
• B) 40 N/m
• C) 30 N/m
• D) 10 N/m

A piano wire 50 cm long has a total mass of 10 g and its stretched with a tension of 800 N. Find the frequency of the wire when it sounds its third overtone note.

• A. 800 Hz
• B. 600 Hz
• C. 400 Hz
• D. 200 Hz

The crackling noise produced by aluminum roofing sheets on a house during a hot sunny day is a result of

• A. thermal equilibrium of the sheets
• B. conduction of heat by the sheets
• C. contraction of the sheets
• D. expansion of the sheets