Calculating Work Done in Pushing a Lawn Mower: A Physics Problem

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A physics problem involves calculating the work done while pushing a 25-kg lawn mower with a force of 400 N at a 45-degree angle for a distance of 12 meters, with a friction coefficient of 0.1. The initial calculations yielded -294 J, while the expected answer is -634 J. A suggestion to draw a free body diagram helped clarify the normal force, leading to the realization of an error in the initial approach. Understanding the forces at play is crucial for accurate work calculation. Correctly accounting for the angle and friction is essential in solving similar physics problems.
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Homework Statement


A woman pushes a lawn mower(25-kg) with a force of 400 N at an angle 45 degrees below the horizontal for a displacement of 12 meters. The coefficient of friction between the lawn and the mower is 0.1. The answer is -634 J but I get a different answer.

Homework Equations


W = F (d)

The Attempt at a Solution


W = -(coefficient of friction) (mg) (12 m)
W = - 0.1 * 25 * 9.8 * 12
W = -294J
 
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master_333 said:

Homework Statement


A woman pushes a lawn mower(25-kg) with a force of 400 N at an angle 45 degrees below the horizontal for a displacement of 12 meters. The coefficient of friction between the lawn and the mower is 0.1. The answer is -634 J but I get a different answer.

Homework Equations


W = F (d)

The Attempt at a Solution


W = -(coefficient of friction) (mg) (12 m)
W = - 0.1 * 25 * 9.8 * 12
W = -294J
You should draw a free body diagram of the lawn mower with the woman pushing it, in order to find the correct normal force.
 
Thank you very much that helped a lot. I realized my mistake.
 

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