A 31.0 kg child slides down a long slide in a playground. She starts from rest a
ID: 2211071 • Letter: A
Question
A 31.0 kg child slides down a long slide in a playground. She starts from rest at a height h1 of 21.00 m. When she is partway down the slide, at a height h2 of 13.00 m, she is moving at a speed of 9.40 m/s. Calculate the mechanical energy lost due to friction (as heat, etc.).
A 31.0 kg child slides down a long slide in a playground. She starts from rest at a height h1 of 21.00 m. When she is partway down the slide, at a height h2 of 13.00 m, she is moving at a speed of 9.40 m/s. Calculate the mechanical energy lost due to friction (as heat, etc.).Explanation / Answer
Loss in Mechanical Energy = mg(h1-h2) - 0.5*m*v^2
= 31*9.8*(21-13) - 0.5*31*9.40^2
= 1060.82 J