A student evaluates a weight loss program by calculating the number of times she would need to climb a 11.0 m high flight of steps in order to lose one pound (0.45 kg) of fat. Metabolizing 1.00 kg of fat can release 3.77 10⁷ J of chemical energy and the body can convert about 22.0% of this into mechanical energy (the rest goes into internal energy.)

HINT

(a)How much mechanical energy (in J) can the body produce from 0.450 kg of fat? J

(b)How many trips up the flight of steps are required for the 90.0 kg student to lose 0.450 kg of fat? Ignore the relatively small amount of energy required to return down the stairs. trips