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## Homework Statement

Suppose that in the same Atwood setup another string is attached to the bottom of m1 and a constant force f is applied, retarding the upward motion of m1. If m1 = 6.45 kg and m2 = 11.90 kg, what value of f will reduce the acceleration of the system by 59%?

## Homework Equations

F

_{net}= ma

## The Attempt at a Solution

So I thought about this problem for quite some time, and then all of a sudden it was BAM I got it! But sadly, my answer was not correct and now I'm here quite disappointed that all my hard work was wrong. Anyway, you probably didn't care to read all that and now I'll just tell you what I did.

I first drew my free body diagrams like a good little Honors Physics student. Then I set up two F

_{net}equations that went something like this:

T = tension

m = mass (subscript denoting mass1 or mass2)

g = gravitational force (9.81)

f = applied force

F

_{net}= T - m

_{1}g - f = m

_{1}(.59a)

which reduced to

T - f = 93.1N

F

_{net}= T + f - m

_{2}g = m

_{2}(.59a)

which reduced to

T + f = 73.7N

Then I added the two reduced equations together to eliminate the f and got T = 83.4N.

Plugging that back into one of the equations, I got f = 9.7N.

If someone could help me out I would really appreciate it! Thanks!