Calculate Work Done by Horse on Level Snowy Surface

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To calculate the work done by the horse pulling a 120kg sleigh on a level snowy surface, the coefficient of kinetic friction is 0.25. The formula for work is W = F * S, where F is the force exerted in the direction of motion and S is the distance traveled. Since the sleigh moves at a constant velocity, the net force is zero, indicating that the force exerted by the horse equals the frictional force. The discussion highlights the importance of understanding the forces acting on the sleigh to determine the work done by both the horse and friction. Ultimately, the user successfully figured out the calculations.
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1. A 120kg sleigh is pulled by one horse at a constant velocity for a distance of 0.75km on a level snowy surface. The coefficient of kinetic friction between the sleigh and the snow is 0.25. (a) calculate the work done by the horse. (b) calculate the work done by friction.



2. F= W * S



3. I really have no idea where to start. Thats all i really want to know. Any hints please?
 
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Shaunzio said:
1. A 120kg sleigh is pulled by one horse at a constant velocity for a distance of 0.75km on a level snowy surface. The coefficient of kinetic friction between the sleigh and the snow is 0.25. (a) calculate the work done by the horse. (b) calculate the work done by friction.
2. F= W * S
Try: Work = Force x distance where Force is the component of force in the direction of motion. Technically, it is: W = \vec{F}\cdot\vec{S}.

Since the sleigh is moving at constant velocity, what does that tell you about the net force on the sleigh?

What are the forces acting on the sleigh? What is the direction of the force exerted by the horse on the sleigh? What is the direction of the force that resists the pull of the horse? What determines the magnitude of this force (of resistance) which the horse is required to provide? Apply the above relation to determine the work.

AM
 
thanks i figured it out :)
 
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