Question

An object falling freely from rest reaches the ground in 2 s. If acceleration due to gravity is 9.8 m s-2, the velocity of the object on reaching the ground will be — (a) 9.8 m s-1 (b) 4.9 m s-1 (c) 19.6 m s-1 (d) Zero

March 14, 2024

Answer

(c) 19.6 m s^-1

Reason — As we know,

The velocity of the object = g × t

Given,

u = 0,

g = 9.8 m s^-2

t = 2 s

v = u + gt

Substituting the values in the formula above, we get,

Velocity of the object = 0 + 9.8 × 2 = 19.6 m s^-1

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