posted by Michele on .
A man drinks a bottle of beer and proposes to work off its 460 kj by exercising with a 20 kg barbell. If each lift of the barbell from chest height to over his head is through 60 cm and the efficiency of his body is 10 percent under these circumstances, how many times must he lift the barbell?
Solve this equation:
(Energy consumed) * 0.10 = Work done
(460*10^3 J)* 0.10 = (number of lifts) * (M g)* (0.60 m)
M = 20 kg and g = 9.80 m/s^2.
Solve for the number of lifts
For some reason not getting it.
I gave you the equation to solve for the number of lifts, and told you what M and g are in the equation. The rest is just doing the numbers.