M1 Dynamics: Find Tension, Friction & Force on Pulley

[T.S.M]

Two particles P and Q of mass 2 kg and 3 kg respectively are connected by a light inextensible string. The string passes over a small smooth pulley which is fixed at the top of a rough inclined plane. The plane is inclined to the horizontal at an angle of 30°. Particle P is held at rest on the inclined plane and Q hangs freely on the edge of the plane with the string vertical and taut. Particle P is released and it accelerates up the plane at 2.5m s−2. Find

a the tension in the string, I got right T = 21.9

b the coefficient of friction between P and the plane, i got it right too 0.418

c the force exerted by the string on the pulley.

Could someone please go through part c?
And if there is a method/rule for part c on all questions that ask this please let me know!
If it would be around a table so pulley would give 90 degree, and so Pythagoras theorem can be applied but its inclined plane :S Can't understand! and one more thing that in finding the this we have to solve it Vector-ically ? or just Pythagoras theorem? I'm really confused, Pls help! :(

 

[tiny-tim]

Hi T.S.M!

c the force exerted by the string on the pulley.

It's just the (vector) difference between the tension on either side.