A sledge loaded with bricks has a total mass of 17.6 kg and is pulled at constant speed by a rope. The rope is inclined at 19.9° above the horizontal, and the sledge moves a distance of 19.5 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is 0.500.
(a) What is the tension of the rope?
N
(b) How much work is done on the sledge by the rope?
kJ
(c) What is the energy lost due to friction?
kJ
2007-10-23 20:17:59 · 2 answers · asked by inpsite 1919 3 in Science & Mathematics ➔ Mathematics
The horizontal component of tension T pulling the sledge is T*cosø. At constant velocity, this equals the frictional force F, and F = k*normal force. The nomal force in this case is the weight of the sledge m*g less the upward lift of the tension T*sinø The resulting equation is then
T*cosø = k*(m*g - T*sinø);
solve for T
T = k*m*g / (cosø + ksinø)
Work done by rope = horizontal force * distance, W = T*cosø * D
this is also the energy lost to friction
2007-10-23 20:41:03 · answer #1 · answered by gp4rts 7 · 1⤊ 0⤋
A Sledge
2016-12-16 14:57:21 · answer #2 · answered by Anonymous · 0⤊ 0⤋