Answer:
Explanation:
Potential energy at the top
PE = mgh = 15.0(9.81)(5.00) = 735.75 J
Kinetic energy at the bottom
KE = ½mv² = ½(15.0)(2.50)² = 46.875 J
Work done by friction is the difference
735.75 - 46.875 = 688.875 ≈ 689 J
HMMMMMmmmm Energy transformation efficiency is 100% because energy can be neither created nor destroyed. With the given answer, I'm guessing they want to know what percentage of the potential energy got converted to heat of friction
688.875 / 735.75 = 0.936289... ≈ 94%
