a block and tackle system of pulleys consisting of 5 pulleys is used to raise a load of 500N through a height of 12m. if the total work done by the system is 7200j calculate the work done against friction and efficiency of the system

Answer 1

work done on the load ... w = f * d = 500 N * 12 m = 6000 J

work against friction = 7200 J - 6000 J

efficiency = 6000 / 7200