A student makes the following claim: “If the net torque on an object is zero
PHYSICS · Single correct · CBSE · Physics · System of Particles and Rotational Motion · System of Particles and Rotational Motion
Problem
A student makes the following claim: “If the net torque on an object is zero, then the object must also experience zero net force.” Which of the following best evaluates the student’s claim?
(a) The claim cannot be evaluated unless the pivot point is specified, because zero net torque depends on the choice of pivot.
(b) The claim is correct because τ=rF; if the vector sum of torques is zero and r=0, the vector sum of forces must also be zero.
(c) The claim is incorrect because an object can have zero net torque and still have a nonzero net force if the forces act along the same line of action.
(d) The claim is incorrect because two equal and opposite forces on opposite sides of the center can make the object translate without producing any torque.