# Work Done on Rough Incline

1. Jul 2, 2015

### Sarah00

1. The problem statement, all variables and given/known data

2. Relevant equations
Conservation of Energy

3. The attempt at a solution

But it is not in the choices, Any Help?

2. Jul 2, 2015

### Nathanael

What is the frictional force on the block?

3. Jul 2, 2015

### Sarah00

I can't find it, as mass is not given.
But mass is not important in the solution, as it will be cancelled from both sides from the equation as shown in my post

4. Jul 2, 2015

### Nathanael

I know, but what did you take the frictional force to be when you calculated the work? Is it correct?

5. Jul 2, 2015

### Sarah00

I did, the change in the mechanical energy is equal to work done by fricton

6. Jul 2, 2015

### Nathanael

So you're saying the frictional force is $\mu_k mg$? The frictional force is $\mu_k F_{normal}$

7. Jul 2, 2015

### Sarah00

Oh yes! That applies on an object resting on horizontal surface with no vertical component of any force is applied. Thanks!!