Static Rigid Bodies Mech Question

I'm a bit stuck on this question! Any help would be great!

A beam AB has weight 40 N and length 3 m. The beam is freely hinged at the end A to a vertical wall. The beam is held in equilibrium at an angle of 60° to the wall by a rope.

One end of the rope is attached to the point C on the beam, where AC = 2 m. The other end of the rope is attached to a point D on the wall, where D is vertically above A.

The rope is perpendicular to the beam, as shown in Figure 1. The rope and the beam lie in a vertical plane that is perpendicular to the wall. The beam is modelled as a uniform rod and the rope as a light inextensible string.

Using the model, find

(a) the tension in the rope,


(b) the magnitude of the resultant force acting on the beam at A.


If the rope was not modelled as being light,

(c) state how this would affect the tension along the rope, explaining your answer.

What have you tried, where are you stuck, ...

for part a :

t = 40cos30 = 20sqrt(3)

I'm not sure if that is correct but I'm stuck on part b

for part a :

t = 40cos30 = 20sqrt(3)

I'm not sure if that is correct but I'm stuck on part b

To get that you appear to have resolved perpendicular to the rod. That means that you should have included the force on the rod at A.

To avoid that, take moments about A and then the force at A won't come into the equation.