How do you find acceleration without knowing the tension?

[tdreceiver17]

My question is how do you find the acceleration if you don't know the Tension. If someone could just elaborate on the question as a whole it would be very helpful.


I didn't really know anything about how to do this problem.

 

[lightgrav]

do you really _not_ know which way it will fall? does it look balanced?

 

[MostlyHarmless]

Start with this notion and see where it gets you: Tension on both sides will be the same, since this pulley is massless/frictionless. Also, in order for the the blocks to move down the 4kg mass side, T must be less than the the weight of the 4kg mass. Make sense?