Aqa As Physics - Tension help?

Hey, I'd be very grateful if you could help me with Tension in physics.

Could you take me through this question, step by step, explaining why you did each part:

http://imgur.com/YoR3Y2c

The black block is the weight the crane is lifting.

I know at the end T1 = 16.5Sin60 and T2 = 16.5Cos60 but I just don't see why

Thanks very much

Reply 1

krisshP

Original post by Varrah

Weight is at rest right, so all force have to be balanced for the equibrium situation. Hence, by Newton's first law resultant force =0N. This can only occur if the upward force of 16.5N is balanced by an equal and opposite force of 16.5kN downwards. Therefore the sum of T1 and T2 horizontally is equal to 0N, but sum vertically is 16.5kN downwards.

Construct a vector triangle. Plug in values. Use the idea of Z alternate angles being the same. You should end up with a nice right angles triangle.