Homework Help: Work done to overcome friction

1. Mar 26, 2013

ms.cupcake

im having a hard time to solve this work done by overcoming friction question. help please?

Question: a block with mass 30kg slide on a rough inclined plane with 8m long and 28 degree to horizontal with acceleration 1.5ms^-2.
a)Calculate the work done to overcome friction.
b)the coefficient of kinetic friction between the block and the plane

2. Mar 26, 2013

voko

Start by writing down the free-body diagram equations.

3. Mar 26, 2013

ms.cupcake

done that and got kE=360.15J

4. Mar 26, 2013

voko

And how does this help?

5. Mar 26, 2013

ms.cupcake

well,the answer for work done to overcome friction is WFf= -745.36J. wonder why was that.

6. Mar 26, 2013

voko

What is the relationship between work, kinetic and potential energy?

7. Mar 26, 2013

ms.cupcake

it helps abit but i got (-745.17J) tho

8. Mar 26, 2013

rcgldr

What value are you using for g (gravitational acceleration)? Perhaps the problem statement is using a different value than what you're using.

9. Mar 26, 2013