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lemon
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Hi:
Would somebody please check to see if I am on the right track with this problem.
Many thanks
An 80kg man on a step-exercise machine climbs a staircase 3.0m high in 8.5s. If he works at the same rate to drive a pedal-operated generator with an efficiency of 75%, how much electrical power would be produced?
power=work done/time taken
efficiency=useful energy output/total energy input
work=force x displacement in direction of force
F=ma
weight=mg (gravity=10ms ^-2)
F=80 x 10 =800N
Work done (W)=800 x 3.0 = 2400J
Power=2400/8.5 = 282.4W (1d.p.)
therefore
75% x 282.4 = 211.8W
F=
Would somebody please check to see if I am on the right track with this problem.
Many thanks
Homework Statement
An 80kg man on a step-exercise machine climbs a staircase 3.0m high in 8.5s. If he works at the same rate to drive a pedal-operated generator with an efficiency of 75%, how much electrical power would be produced?
Homework Equations
power=work done/time taken
efficiency=useful energy output/total energy input
work=force x displacement in direction of force
F=ma
weight=mg (gravity=10ms ^-2)
The Attempt at a Solution
F=80 x 10 =800N
Work done (W)=800 x 3.0 = 2400J
Power=2400/8.5 = 282.4W (1d.p.)
therefore
75% x 282.4 = 211.8W
F=