Physics Past Questions and Answers

A few grains of table salt were put in a cup of cold water, kept at constant temperature and left undistributed. Eventually all the water tested salty. This action is due to?

A Convection
B Osmosis
C Capillarity
D Diffusion

Question 2:

The force required to make an object of mass m, travelling with velocity v, turn in a circle of radius r is

A \(\frac{mv^2}{r}\)
B \(\frac{mr^2}{x}\)
C \(\frac{mr}{v}\)
D \(\frac{mv}{r^2}\)

Question 3:

A machine gun with a mass of 5kg fires a 50g bullet at a speed of 100 ms\(^{-1}\). The recoil speed of the machine gun is

A 0.5 ms\(^{-1}\)
B 1.5 ms\(^{-1}\)
C 1 ms\(^{-1}\)
D 2ms\(^-1\)

Question 4:

If in a simple pendulum experiment the length of the inextensible string is increased by a factor of four, its period is increased by a factor of?

A 4
B \(\frac{\pi}{2}\)
C \(\frac{1}{4}\)
D 2

Question 5:

In what range of temperature is the expansion of water anomalous?

A +208\(^o\)C to +212\(^o\)C
B -80\(^o\)C + -76\(^o\)C
C 0\(^o\)C to +4\(^o\)C
D -4\(^o\)C to +0\(^o\)C