Velocity of an object dropped from a building at any instant "t" is given by:
Correct answer: D. gt
- A. 1/2 gt2
- B. vit +1/2 gt2
- C. t2
- D. gt
Explanation
The correct answer is gt. When an object is dropped from rest, its initial velocity (vi) is zero. The acceleration acting on the object is due to gravity (g). Thus, the velocity at any time 't' is given by the equation Vf = Vi + at, where 'a' is replaced by 'g'. Since Vi is zero when the object is dropped, the equation simplifies to Vf = gt.Option A (1/2 gt2) calculates the distance fallen, not the velocity. Option B (vit + 1/2 gt2) is a formula for distance with initial velocity, which does not directly give velocity. Option C (t2) lacks any consideration of gravitational acceleration and hence does not represent velocity.
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