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Question

anonymous · Answer

Two rollers of the same diameter are supported by an inclined plane and a 
vertical wall as shown in figure given below. The upper and lower rollers are respectively 
200 N and 250 N in weight. Assuming Smooth surfaces, find the reactions induced at the 
points of support A, B, C and D.

theeric · Answer

Hello! So there are three principles involved here: normal forces, equilibrium (no net force), and splitting forces into their components.

theeric · Answer

The other two things is knowing that the reactive force is the force produce "in reaction" to another. Look to Newton's Third Law. Forces come in pairs, as Wikipedia says. Your pairs are the weights paired with the normal forces, to be general. The second thing is that I don't see a point $D$.

theeric · Answer

I guess Newton's Third Law would also be a main concept.

theeric · Answer

So, where are you experiencing a problem?