Answer:
a) 0.5 J
b) 99.5%
Step-by-step explanation:
a) The energy being wasted is the difference between the starting potential energy and the ending kinetic energy:
100 J -99.5 J = 0.5 J
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b) If we consider the efficiency to be the ratio of ending kinetic energy to beginning potential energy, it is ...
99.5 J/(100 J) = 99.5/100 = 99.5%