science
Grade-9
Easy
Question
Peter wants to modify the formula for acceleration
i.e., a = (v – u)/ t
Where v = final velocity, u = initial velocity, t= time, a = acceleration, to suit the special case of freefall of a ball dropped from the top of a building. He chooses to make the following substitutions in the formula.
a. v= 0
b. u= 0
c. a= 9.8 m/s2
Identify the correct substitutions.
- Speed = magnitude of velocity
- Distance covered = displacement
- Acceleration = 0
- All of the above
Hint:
Speed = magnitude of velocity
The correct answer is: Speed = magnitude of velocity
In the case of freefall, speed becomes equal to same as the magnitude of velocity as there is no change in direction.
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