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A force F is applied to a dumbbell for a...

A force `F` is applied to a dumbbell for a time interval, `t` as in `(i)` and then as in `(ii)`. In which case does the dumbbell acquire the greater centre-of -mass speed ?
.

A

(i)

B

(ii)

C

there is no difference

D

the answer depends on the rotional inertia of the dumbbell

Text Solution

Verified by Experts

The correct Answer is:
C

`a_(cm) = (Ft)/(2 m)`
which is same in both cases
`v_(cm) = a_(cm) t`
so speed of centre of mass will be same in both cases.
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