A 15.0kg box slides down an incline 5.00 m high and 9.00 m long. It starts at rest at the top and moves at the speed 2.50m/s when it is at the bottom. How much work is done by friction? [688J].
What is the energy transformation efficiency? [94%]

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

H 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%

b

explanation:

bc its just b

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