Question

the figure below shows two blocks suspended by a single cord over a pulley. (figure 1) the mass of block b is twice the mass of block a, while the mass of the pulley is equal to the mass of block a. the blocks are let to move and the cord moves on the pulley without slipping or stretching. there is no friction in the pulley axle and the cords weight can be ignored. which of the following statements correctly describes the system shown in the figure? check all that apply. view available hint(s) the acceleration of the blocks is zero. the net torque on the pulley is zero. the angular acceleration of the pulley is nonzero. submit part b - complete previous part(s) provide feedback

Explanation:

Step1: Analyze forces on blocks

Since block B has a greater mass ($2m$) than block A ($m$), there is a net - force acting on the system of blocks. According to Newton's second law $F = ma$, the blocks will accelerate. So the acceleration of the blocks is non - zero.

Step2: Analyze torque on pulley

The tensions in the cord on either side of the pulley are different due to the different masses of the blocks. The net torque $\tau= rF_{\text{net}}$ (where $r$ is the radius of the pulley and $F_{\text{net}}$ is the net tangential force) on the pulley is non - zero. Since $\tau = I\alpha$ (where $I$ is the moment of inertia of the pulley and $\alpha$ is the angular acceleration), and $I
eq0$ and $\tau
eq0$, the angular acceleration of the pulley $\alpha$ is non - zero.

Answer:

The angular acceleration of the pulley is nonzero.