Question

What will be the final velocity of a rock if we drop it off of a bridge and it strikes the ground 2.8s later (ignoring air resistance)?

Answer 1

Formula for final velocity: Vf= vi+(a*t)
Vi- initial velocity, a=acceleration, t-time

Vf=vi+(at)
Vf= 0+(9.8m/s*2.8s)
Vf= 27.44 m/s

The acceleration of the Earth when dropping something would be 9.8 m/s

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