# Homework Help: Conservation of energy of a marble problem

1. Jul 30, 2009

### Amar.alchemy

1. The problem statement, all variables and given/known data
A uniform marble rolls down a symmetric bowl, starting from rest at the top of the left side. The top of each side is a distance h above the bottom of the bowl. The left half of the bowl is rough enough to cause the marble to roll without slipping, but the right
half has no friction because it is coated with oil. (a) How far up the smooth side will the marble go, measured vertically from the bottom?

2. Relevant equations

Conservation of energy

3. The attempt at a solution
While applying conservation of energy, why we should not consider the work done by the friction force on the marble? Kindly explain me.

2. Jul 30, 2009

### kuruman

Because the marble rolls without slipping, there is no heat generated at the point of contact so no Joules are lost to friction. For heat to be generated, the two surfaces need to rub against each other.

3. Jul 30, 2009

### Amar.alchemy

ok, Thanks :)