2 masses on an inclined plane, one unknown mass needs to be found

[oconnc59]

Homework Statement

see attached diagram, one mass is given at 10 kg while the other is unknown. The friction is given an (mu)=0.25 for both masses

Homework Equations

i need to find Magnitude of M for when the 10KG Mass slides down the plane and again for when the 10KG mass slides up the plane

The Attempt at a Solution

on the 10kg mass
mgsin(thetha)=49.05
mgcos(thetha)=84.96

I don't know where to go from here, I am really stuck with this can anyone help please?

On the Unknown Mass
mgsin(thetha)=8.5m
mgcos(thetha)=4.905m

 

[diazona]

It would be appreciated if you didn't post diagrams as MS Word files. There's a whole list of image formats which are much better for this sort of thing.

From your diagram (at least, as well as I can make out - it came through rather distorted), I can't see what the unknown mass M has to do with anything. Is there some information in the problem you're not telling us? Are the two masses connected by a string, perhaps?

Also, when you calculate the components of the gravitational force, make sure you have the correct units. (You don't in the post above)