A mover uses a pulley to lift a 2,400 Newton piano up to the second floor. Each time he pulls the rope down 2 meters (input distance), the piano moves up 0.25 meters (output distance). With what force does the mover pull on the rope?

Question part points submissions used suppose that 2 j of work is needed to stretch a spring from its natural length of 26 cm to a length of 36 cm. (a) how much work is needed to stretch the spring from 28 cm to 32 cm? (round your answer to two decimal places.)

Estimate of the number of stars in our galaxy

Describe the work performed by a ski lift in terms of kinetic and gravitational potential energy