Solve Friction Work Problem: Boy Pulls Wagon 25.0kg 20.0m 60.0N 0.214

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To solve the problem of the boy pulling a 25.0kg wagon with a force of 60.0N at a 40.0° angle over 20.0m, the work done can be calculated using the equation W=FdCos(theta). The friction coefficient of 0.214 is noted, but the problem is considered overspecified, as not all information is necessary for the solution. Balancing forces can also be used to find the normal and friction forces, which should equal the horizontal pull from the boy. Ultimately, using the provided force and distance yields the correct work calculation. The discussion highlights the frustration with excessive information in physics problems.
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Homework Statement


A boy pulls his wagon of mass 25.0kg at a constant velocity a distance of 20.0m. the wagon's handle makes an angle of 40.0° with the ground while the boy is pulling on it with a force of 60.0N. The coefficient of friction is 0.214. how much work did the boy do on the wagon

Homework Equations



W=FdCos(theta)

The Attempt at a Solution



Not sure where to start. I am not sure where the friction fits in.
 
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As written, this is what's known as an "overspecified" problem. There is actually more information given than what is required.

Using F d cosθ, using the given 60.0 N force, will work just fine.

Alternatively you could balance the forces to find the normal and friction forces. The friction force should balance the horizontal pull from the boy ... though they turn out to be slightly different using the numbers given here (?).
 
Alright that makes scene. It worked out for me. I hate the extra stuff in problems.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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