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## Homework Statement

A child whose weight is 269 N slides down a 6.80 m playground slide that makes an angle of 41.0° with the horizontal. The coefficient of kinetic friction between slide and child is 0.190. (a) How much energy is transferred to thermal energy? (b) If she starts at the top with a speed of 0.314 m/s, what is her speed at the bottom?

## Homework Equations

ke=1/2 mv

^{2}

thermal energy = f

_{k}d = f

_{n}U

_{k}d

## The Attempt at a Solution

for b I used 1/2mv

_{i}

^{2}+ mgh - f

_{k}d = f

_{n}U

_{k}d = 1/2mv

_{f}

^{2}

and got it correct...

I missed the class where the teacher explained thermal energy and frictional energy so I assumed that the energy lost to friction is turned into thermal energy and i used

thermal energy = f

_{k}d = f

_{n}U

_{k}d

plugged everything in and got 228 J...

but maybe i have the relationship wrong?