Please help me, this is due tonight at 11 and I can't figure out what to do!(adsbygoogle = window.adsbygoogle || []).push({});

" A 17 kg child descends a slide 3.5 m high and reaches the bottom with a speed of 2.5 m/s. How much thermal energy due to friction was generated in this process?"

The equation should be:

kinetic energy intiial + potential energy initial = ke (final) + pe (final) + friction X distance travelled

so

1/2mv^2 (initial) + mgy (initial) = 1/2mv^2 (final) + mgy(final) + Friction X d

The problem is I don't know d!

0 (no initial KE) + (9.8)(17)(3.5) = 1/2(17)(2.5)^2 + 0 (no final potential energy) + friction X d!

What is D!

I tried making the slide a right triangle with 45 degree angles for the other two and using the pythagorean theorem...and got 5 for the distance..but I got a wrong answer..

huh, could someone PLEASE help me!

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# Homework Help: Help Please! Energy Conservation!

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