Calculating Forces and Acceleration in a Two-Block System

[Questions999]

Homework Statement

The constant force that works in the object M=5 kg forces the object with mass m=4 kg to move with acceleration a=2 m/s^2.
The coefficient of friction between M and the table is 0.2.
Determine
a)F=? b) T=?

Homework Equations

The Attempt at a Solution

SOLUTION:
F-Ff=(m)*a Here I find F
and here I find F
B) F-(T+Ff)=m*a or T=m2*g ;G-T=m*g

Picture to help you http://i1171.photobucket.com/albums/r549/Elaia06/jh.jpg

Edited: Maybe it is F-Ff=(m+M)*a where Ff =M*g*0.2?

 

[PhanthomJay]

Draw a free body diagram of each mass separately (one for m and one for M). For the mass on the table, there is another force besides F and F-f acting in the x direction. For the hanging mass there are 2 forces acting. Use Newton 2 for each and solve the 2 equations for the 2 unknowns.

 

[Questions999]

I know,its also the tension but I want to know if my equations are written in the right way?

 

[PhanthomJay]

They are not. First distinguish between m and M. Write your force equations for each block.

 

[Questions999]

I edited it

 

[PhanthomJay]

Do not solve it this way. You will be headed for trouble. Look at each block separately please.