Question

The rod AB of length and mass m can rotate freely about A in a vertical plane. A point mass m is
attached to the other end of the rod and the system is released from its horizontal position. The initial
angular acceleration is​

Answer 1

Answer:

9g/8l

Explanation:

Answer 2

Answer:

the initial angular acceleration is 9g/8l

Explanation:

let, α be the angular acceleration

    I be rotational inertia

we know, torque, T =α I

     T= α(ml^2+ml^2/3)

     T= α(4/3*ml^2)    -------1

we also know, T= force * length

     T= mg l +mg l/2

     T= 3/2* mg l    --------2

from 1and 2

3/2*mg l = α(4/3*ml^2)

α = 9g/8l