Question

A 5 kg mass is resting on a table, the coefficient of friction between the block and the table is 0.25, that block is connected to a 10 kg hanging mass over a string by a pulley as shown in the picture. What is the acceleration of the 5 kg mass?

Answer 1

$$(m+M)a=Mg-\mu mg=(M-\mu m)g\\(5+10)a=(10-0.25(5))9.8\\a=5.7\frac{m}{s^2}$$