Question

5. A body falls freely from rest. It covers as much distance in the last second of its motion as covered in the first
three seconds. The body has fallen for a time of:
A) 3s
B) 5s
C) 7s
D) 9s
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Answer 1

Answer:

Explanation:9s

Answer 2

Answer:

Answer is B) 5s

Explanation:

Distance covered in first 3 sec.

S = 1/2gt^2 = 1/2x9.8x3x3

distance covered in last second

S =9/2(2t-1)

1/2x9.8x9 =9/2(2t-1)

t = 5.4

t is nearly about 5

therefore t = 5sec.