Question

A 6.0 𝑘𝑔 body rests on a smooth horizontal tabletop. A horizontal cord attached to the body passes over a light frictionless pulley at the edge of the table to 12.0 𝑘𝑔 body hanging freely. Find the acceleration and the tension in the cord when the system is released. 

Answer 1

For the two bodies, write forces by Newton's second law:

$$T=ma,\\ -Ma=-Mg+T,\\\space\\ a=g\frac{M}{M+m}=6.5\text{ m/s}^2,\\ T=39.2\text{ N}.$$