Question

If F is the force acting on the particle having position vector r and τ be the torque of this force about the origin then 1) r.τ >0, and F. τ < 0 2) r.τ =0 , F.τ =0 3) r.τ =0, F.τ not equals to 0 4) r.τ not equals 0, F.τ =0

Answer 1