A horizontal rod of mass M and length L is tied to two verticle string symmetrically as shown in the figure. One of the strings at end Q is cut at `t=0` and the rod starts rotating about the other and P then

Options

A. At `t=0` angular acceleration of rod about P is `3g//2L`
B. At `t=0` angular acceleration of rod about C.M. of rod is `3g//2L`
C. At `t=0` acceleration of C.M. of rod is `3g//4` in downward direction.
D. At `t=0` tension in the string at P is `Mg//4`

Answer

A, B, C, D

Explanation

`Mg(L/2)=((ML^(2))/3)alpha`
`:.alpha=(3g)/(2L):.a_(cm)=(alphaL)/2=(3g)/4`
`-T+Mg=M((3g)/4):. T=(Mg)/4`