Question

A rope 9m long is connected at A and B,two points on the same level,8m apart.A load of 300N is suspended from a point C on the rope ,3m from A . What load connected to a point D , on the rope , 2m from B is necessary to keep portion CD parallel to AB.

Answer 1

Given:

Length of the rope = 9m

Distance between A and B points = 8m

Load at point C = 300N

Distance of C from point A = 3m

To find:

Load connected to point D on the rope, 2m from point b to keep CD parallel to AB.

Solution:

Considering the moment at the point A about C.

Ma = load* distance of CA = 300*3=900

To maintain equilibrium the moments of Load at C and D will be same about point BA

Now moment of load D about point A will be

Ma = load*distance of AD

900 = load * (8 - 2)

load = 150N

Therefore the required load connected to point D must be 150N.