How Does Tension Work in a Pulley System?

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[SOLVED] Tension Question(s)

I'm kind of confused about how tension works.

For example,

If I had two blocks that massed 5kg hanging on either side of a frictionless pulley, what would be the tension of the rope connecting them? If one of the blocks massed 2kg and the other were 5kg, what would be the tension?

(I'm not asking for you all to do all of the calculations for these two examples - I'm just wondering what the general method for solving these types of problems is and how tension works)

EDIT: Nevermind. With some searching, I found that T= (2*m1*m2)/(m1+m2)*9.8
 
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bfr said:
If one of the blocks massed 2kg and the other were 5kg, what would be the tension?

Keep in mind that, while the equation will give you an answer to this question, there is a net upward force on the 2kg block and a net downward force on the 5kg block. This is because the calculated tension on the rope acts upward on both blocks, but it pulls harder on the 2kg block than gravity does and it pulls less hard on the 5kg block than gravity does, so the whole system moves.

The acceleration of the blocks are opposite in direction and equal in magnitude.

Hey, for extra credit, find the magnitude of the acceleration.