A triangular plate of uniform thickness and density is made to rotate about an axis perpendicular to the plane of the paper and
(i) passing through `A`,
(ii) passing through `B`, by the application of some force `F` at `C` (mid - point AB) as shown in the figure. In which case angular acceleration is more ?
.

Options

A. angular acceleration in both the cases is the same
B. angular acceleration for case (a) is larger
C. angular acceleration for case (b) is larger
D. there would be no angular acceleration for case (a)

Answer

C

Explanation

`tau=Fd tau` is same in magnitude for both cases.
Also` tau=Ialpha`
so `Ialpha` is constant.
For case `b` I is small.
so `alpha` is large