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Bluesroo

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This is incredibly simple, but i cannot remember the formula for tension, which is a show stopper.

Simple pulley. Two masses attached with a string running over a frictionless wheel. m1 is 8kg and m2 is 12kg. I need to find acceleration and tension over the string.

F= ma

anet= (Fg2-Fg1)/(m1+m2)

T= Fnet1+Fg1 or T= Fnet2-Fg2 (I don't think these are right)

F= ma

Fg1= 8kg* 9.8m/sec^2

Fg1= 78.4N

Fg2= 12kg* 9.8m/sec^2

Fg2= 117.6N

anet= (Fg2-Fg1)/(m1+m2) (at second glance this seems like a faulty equation as well...)

anet= (117.6N-78.4N)/(8kg+12kg)

anet= 1.96m/sec^2

Now I can't find tension because I'm not sure where Fnet comes from (the sum of Fg1 and Fg2?) nor do I have the formula for tension written down... I didn't take very good notes on this (surprise surprise )

## Homework Statement

Simple pulley. Two masses attached with a string running over a frictionless wheel. m1 is 8kg and m2 is 12kg. I need to find acceleration and tension over the string.

## Homework Equations

F= ma

anet= (Fg2-Fg1)/(m1+m2)

T= Fnet1+Fg1 or T= Fnet2-Fg2 (I don't think these are right)

## The Attempt at a Solution

F= ma

Fg1= 8kg* 9.8m/sec^2

Fg1= 78.4N

Fg2= 12kg* 9.8m/sec^2

Fg2= 117.6N

anet= (Fg2-Fg1)/(m1+m2) (at second glance this seems like a faulty equation as well...)

anet= (117.6N-78.4N)/(8kg+12kg)

anet= 1.96m/sec^2

Now I can't find tension because I'm not sure where Fnet comes from (the sum of Fg1 and Fg2?) nor do I have the formula for tension written down... I didn't take very good notes on this (surprise surprise )

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