A girl and her bicycle have a total mass of 40.0 kg. At the top of the hill her speed is 5.0 m/s, and her speed doubles as she rides down the hill. The hill is 12.0 m high and 100 m long. How much kinetic energy and potential energy is lost to friction?

a. 2420 J
c. 2000 J
b. 3200 J
d. 3920 J

B

Physics & Space Science

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