Question

Two identical bodies of mass m are joined by a string passing over a pulley with a fixed axis. An additional mass m is placed on one of the masses

Answer 1

Explanation:

All the bodies of the system move with the same acceleration.

On the mass M on the left act the force Mg due to its weight and the tension T in the string; on the mass on the right act the force Mg due to its weight, the force f of the additional mass and the tension T in the string. Acting on the additional mass m are the force mg due to its weight and the force f from the mass M. The equations for Newton's second law for each of the three masses are

T— Mg = Ma, 

Mg+f—T= Ma, 

mg — f = ma.

The solution of these equations determines the values of a, T, and f. 

The force on the pulley axis is double the tension in the string: F = 2T