Physics
posted by Francis on .
a bike is 25% efficient in converting energy of the bicyclist to mechanical energy. If a cyclist is travelling along a pathway at a constant speed of 5.8 m/s for 3600 s, and the average resistance is 22 N, how much mass does she lose assuming 1 kg is lost for each 2.9 x 10^7 J of energy she uses?

The bike does 22*5.8*3600 joules work.
She does 4 times that amount of energy, or
4*22*5.8*3600 joules.
Weightlost? 4*22*5.8*3600/2.9E7= not much. 
Thank you so much!