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Frc31 Three mass problem

Take the three masses and two cords as shown below.

Find the acceleration of the system and the tension in the cords.

There are two cords and two separate tensions.

Take the motion to the right, clockwise. Find the component of the gravitational force on the 25 kg down the plane.

Draw the force diagrams for the three masses.

Now there are three equations to write. Remember the direction is clockwise.

These three equations in three unknowns are most conveniently solved by adding (1) and (2)

and then combining this with (3)

The tension in the cords is from equations (1) and (3).