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1. Aball tied with a string to a rotating shaft revolves at uniform speed. As the shaft is suddenly brought to rest the string starts getting round the shaft with the angular velocity of the ball.
(A). increasing
(B). decreasing
(C). remaining constant
(D). becoming zero

2. If an apple is released from an orbiting spaceship, it will
(A). fall towards the earth
(B). move along with spaceship at the same speed
(C). move at a higher speed
(D). move at a lower speed

3. What happens when water is cooled from 8° C to 0° C?
(A). Its volume decreases uniformly, becoming minimum at 0° C
(B). Its density increases uniformly, attaining maximum value at 0° C
(C). Its volume decreases upto 4° C and then increases
(D). Its density decreases upto 4° C and then increases

4. During summer, we feel comfortable under a fan because it -
(A). throws cool air on us
(B). sets the air in motion, thereby increasing the evaporation of sweat
(C). produces convection currents
(D). produces air which carries heat away from the body

5. Light waves are different from sound waves in that
(A). light waves are electromagnetic but sound waves are not
(B). light waves can travel through water but sound waves cannot
(C). light travels with the same speed in all media
(D). light waves produce interference but sound waves do not