an elevator starts at the ground floor and carries a 70 kg man to the 2nd floor and a 40 kg man to the 8th floor. at the 8th floor, 3 men, 65 kg each get on the elevator and descend to the 4th floor and get out. the empty elevator then goes to the ground floor. what is the total work that the elevator did?

Question

shane_b · Answer

How far apart are the floors?  Since W = Force * distance, you need to know that.

anonymous · Answer

each floor is four meters high. thank you

shane_b · Answer

The formulas and constants you need are:
$$Force=mass * acceleration$$$$Work =force *distance$$$$acceleration = -9.8 m/s^2$$
To solve it just compute the work for each part of the trip and sum up the values.

anonymous · Answer

work going up = 110*4*9.8 + 40*28*9.8+ 195*(9.8-elevator acceleration)*16