Question

8. 12 A body falls for 5 s from rest. If the acceleration due to gravity of earth ceases to travels in the next 3 s is a) 73.5 m b) 294 m c) 147 m in the ratin 2-1 are dropped simultaneously at ) 147 d) 49m
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Answer 1

Explanation:

Correct option is D)

Initially the body starts its motion from rest therefore u=0. Let journey be A when a acceleration of earth is acting on the body time =5 seconds let's find v

v=u+at

=0+9.8×5=49m/s

When acceleration stops acting the velocity of the body is 49m/s. Now the distance traveled by the body in next 3s

S=ut+

2

1

gt

2

=49×3+

2

1

×0×t

2

=49×3

=147m.