Applied force on two blocks on a horizontal frictional plane

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Homework Statement


Two blocks connected by a string are pulled
across a rough horizontal surface by a force
applied to one of the blocks.
The acceleration of gravity is 9.8 m/s2 .
1st block = 2 kg
2nd block = 8 kg
Force on second block at 52◦
μ = 0.29

[ 2kg ]-------[ 8kg ]/ 52 degrees

If each block has an acceleration of 1.6 m/s2
to the right, what is the magnitude of the
applied force? Answer in units of N.

Homework Equations


The Attempt at a Solution



What I got was 72.15 N but I got it wrong and I have no idea what I did wrong
 
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Draw a fbd and sum the forces for each block in the x and y.
 
Jebus_Chris said:
Draw a fbd and sum the forces for each block in the x and y.

what do i use for the force against friction for the block being pulled?
 
You need to find an expression for the normal force. In the y direction the force of gravity acts downward, the normal force acts upward, and the applied force acts upward.
 
ok for the 8kg block i got 39.30N the problem that i am having for the 2kg block is that i do not no what Force I am solving for that is pulling the block is it Fcos60 like the previous one or is it the tension of the string
 
The tension in the string is pulling the second block.
 
would you find that simply by multiplying mass times acceleration of the 2kg block?
 
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