The torque `tau` on a body about a given point is found to be equal to AxxL where A is a constant vector, and L is the angular momentum of the body about that point. From this it follows that

The torque tau on a body about a given point is found to be equal to A x L, where A is constant vector and L is the angular momentum of the body that point. From this, it follows that

The torque vec tau on a body about a given point is found to be equal to vec A xx vec L where vec A is a constant vector and vec L is the angular momentum of the body about the point. From this its follows that -

Angular momentum of a planet about the point of it's apogee is

The angular velocity of a rigid body about any point of that body is same :

The angular velocity of a rigid body about any point of that body is same :

Torque (vec tau) acting on a rigid body is defined as vec tau = vec A xx vec L , where vec A is a constant vector and vec L is angular momentum of the body. The magnitude of the angular momentum of the body remains same. vec tau is perpendicular to vec L and hence torque does not deliver any power to the body.

Obtain tau=Ialpha from angular momentum of rigid body.