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.
Last updated
About Force and Motion
Displacement, velocity and acceleration describe motion, including the horizontal and vertical components of projectile motion. The chapter connects these quantities with Newton's laws, momentum and impulse, then applies conservation of momentum to collisions, distinguishing elastic collisions from inelastic ones.
Practise Force and Motion
1,416 free Force and Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
(1, 1, 1) . (2, 2, 2)
1st law of motion gives the definition of:
2nd law of motion measures which quantity?
7.0 kg bowling ball experience a net force of 5.0N. What will be its acceleration?
A 0.2 kg rubber ball is dropped from the window of a building. It strikes the sidewalk below at 30m/s and rebounds up at 20m/s. The impulse on the ball during the collision is: