- #1
confusedbyphysics
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Please help me, this is due tonight at 11 and I can't figure out what to do!
" 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!
" 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!