This is a two part question: 1. With a simple pulley system using one pulley - say 10000 kg on each side - the ability to pull either one up or down to change the position is theoretically just the friction on the system and any extra length of rope on one side? 2. Would it be more work lost on pulling up a large weight (i.e. 1 million Kg) with a 1 pulley system with equal weight on each side OR would it be more work on a multiple compound pulley system? --- The goal of my question in part 2 is whether one large weight on a single pulley would mean more friction than a lighter counterweight...but it has more pulleys for the rope to run through?