posted by Anonymous .
a crane does 62,500. J of work lifting a 120.-N backpack?
a. How high did you lift the backpack?
b. How much did the backpack weigh in pounds? (Hint: There are 4.448 N in one pound.)
a. 62,500 J = M g H
M g = 120 N.
Solve for H
b. 120 N/4.448 N/lb = ____lb