posted by Chan on .
Please help me I have no idea how to do this problem at all.
Question:A sledge loaded with bricks has a total mass of 17.8 kg and is pulled at constant speed by a rope inclined at 20.8° above the horizontal. The sledge moves a distance of 20.6 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is 0.500.
(a) What is the tension in the rope?_ N
(b) How much work is done by the rope on the sledge?__ kJ
(c) What is the mechanical energy lost due to friction?__KJ
you start by breaking up the tension in the rope into a vertical part (which reduces force normal and friction), and a horizontal part.
Forcenormal=mg-vertical component of tension
so to move, the horizontal component of tension must at least equal fricion.
You can now find tension from that.
work on sled? tensioninhorizontal*distance.