Calculating Time for a Person Pulling a Lawn Mower

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A person pulls a 20kg lawnmower with a force of 25.0N at a 15-degree angle, moving it 4.50 meters while overcoming a friction coefficient of 0.100. The work done by the person is calculated to be 109J, while the work done against friction is -85.3J. To find the time taken to move the mower, the net horizontal force and kinematic equations are suggested as potential methods. Ultimately, the time required to pull the lawnmower is determined to be 5.89 seconds. This calculation illustrates the relationship between work, force, and time in a practical scenario.
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Homework Statement


A person pulls on a 20kg lawnmower with a force of 25.0N and moves the mower 4.50metes. The handle angle is 15* with the horizontal and μ=0.100.
a) Work done by person √ = 109J
B) Work done by friction √ = -85.3J
C) Find the time ?


Homework Equations


P= W/T = W*(constant velocity)

The Attempt at a Solution



I tried to use one of the power equations though I had 2 unknowns (P and T). I have no idea how to go about finding the time.
 
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zaddyzad said:

Homework Statement


A person pulls on a 20kg lawnmower with a force of 25.0N and moves the mower 4.50metes. The handle angle is 15* with the horizontal and μ=0.100.
a) Work done by person √ = 109J
B) Work done by friction √ = -85.3J
C) Find the time ?


Homework Equations


P= W/T = W*(constant velocity)

The Attempt at a Solution



I tried to use one of the power equations though I had 2 unknowns (P and T). I have no idea how to go about finding the time.

What's the net horizontal force on the lawnmower? What then is the motion? Can you think of a suitable kinematic equation to find the time given the distance traveled?
 
Thank you very much for the help :D. Got it 5.89s
 

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