Let `vec(F)` be the force acting on a particle having position vector `vec(r )` and `vec(tau)` be the torque of this force about the origin. Then

Options

A. `vec(r ).vec(F)=0` and `vec(r ).vec(tau)ne0`
B. `vec(r ).vec(tau)ne0` and `vec(F).vec(tau)=0`
C. `vec(r ).vec(tau)ne0` and `vec(F).vec(tau)ne0`
D. `vec(r ).vec(tau)=0` and `vec(F).vec(tau)=0`

Answer

D