An aeroplane is flying horizontally with a velocity of 600 km/h and at a height of 1960 m. When it is vertically at a point A on the ground a bomb is released from it. The bomb strikes the ground at point B. The distance AB is

A. 1200 m
B. 0.33 km
C. 3.33 km
D. 33 km


Rain is falling vertically downwards. To a man running east-wards, the rain will appear to be coming from

A. east
B. west
C. northeast
D. southeast


Intensity of sound has

A. an object existence
B. a subject existence
C. no existence
D. both subjective and objective existence


Minimum number of unequal vectors which can give zero resultant are

A. two
B. three
C. four
D. more than four


It is easier to roll a barrel full of coal tar than to pull it because

A. the full weight of the barrel comes into play when it is pulled
B. the rolling friction is much less than the sliding friction
C. more surface area of the barrel is in contact with the road when it is pulled
D. coal tar is a liquid and it flows in the barrel when it is rolled