Reduce system to a single force and couple:

Q: A system of parallel forces is acting on rigid bar as shown in the figure given below. Reduce this system to a single force and couple

A single force and couple at A:  It means the whole system is to convert in to single force and a single couple.

As we convert all forces in to single force that is resultant.

Now apply the two equal and opposite force that is 'R' at point A. Now force 'R' which is acting at point E and upward force which is acting at point A makes a couple of magnitude,

Magnitude = Force × distance = 60 × 0.833

= 49.98 Nm     .......ANS       and single force of magnitude = 60N          ........ANS