Finding acceleration and tension using Newton's laws

AI Thread Summary
The discussion focuses on solving a physics problem involving acceleration and tension using Newton's laws. The user has broken down the system into two parts, applying Newton's second law to each block but encounters three unknowns (tension, force, and acceleration) with only two equations. There is uncertainty about whether tension is consistent on both sides of the rope, which is affirmed as a valid assumption for a massless rope. The user is advised to consider the given force and revisit the equations to find a solution. Taking a break is suggested to gain clarity on the problem.
Mangoes
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Homework Statement



http://i.imgur.com/sPN07Hi.png

Homework Equations



Newton's laws of motion.

The Attempt at a Solution



I split up the entire thing into two pieces.

http://imgur.com/dMxfCZM

The left diagram illustrates the left block of 3 kg. I set the x-axis parallel to the ramp. The right is of the right block, where the x-axis is taken to be parallel to the horizontal surface.

Since accelerations occurs on the system,

By the left illustration,
ƩFx = T - w1sin30 = m1a

and by the right illustration,
ƩFx = Fcos20 - T = m2a

I can substitute the masses by their respective quantities, but my problem is that I have three unknowns (T, F, and a) and only two equations. I also don't really see how using the vertical components of motion will help me out.

Also, one thing I'm not even completely sure about is whether it's even correct to assume that tension is the same on both sides of the rope.

What am I doing wrong in here?
 
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Mangoes said:
I can substitute the masses by their respective quantities, but my problem is that I have three unknowns (T, F, and a) and only two equations.
F is given. Look at the diagram.

Also, one thing I'm not even completely sure about is whether it's even correct to assume that tension is the same on both sides of the rope.
For a massless rope, that is a good assumption.
 
Okay I think it's time to take a break then...

Thanks for the help.
 
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