A85.0 kg window washer hangs down the side of a building from a rope with a cross-sectional area of 4.00×10−4 m2. if the rope stretches 0.740 cm when it is let out 7.50 m, how much will it stretch when it is let out 21.0 m?

You carry a 7.0-kg bag of groceries 1.2 m above the ground at constant speed across a 2.7m room. how much work do you do on the bag in the process? (a) 157j (b) 0.00j (c) 185j (d) 82j

If a sphere and a cure have the same mass and are propelled up a ramp with the same force, which would travel father up the ramp? explain.

Afeather of mass 0.001 kg falls from a height of 2 m. under realistic conditions, it experiences air resistance. based on what you know about friction, what can you say about the kinetic energy of the feather as it reaches the ground? acceleration due to gravity is g = 9.8 m/s2. a. ke < 0.0196 j b. ke = 00196 j c. je = 0 j d. ke > 0.0196 j