After reading your comment and re-reading the question, I see where I went wrong.
In the previous bit of the question you have to work out the coefficient from acceleration and the force acting down the slope using F=ma
Force down slope-Friction=mass x acceleration
But if you have air...
Homework Statement
The question asks me to work out the coefficient of friction for a block accelerating down a rough slope assuming their is no air resistance, which I could do easily. In the next part it then asks how the coefficient would change if their was air resistance
Homework...