Calculating Acceleration and Work for a Box on a Horizontal Surface

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The problem involves calculating the acceleration and work done on a 125 N box being pulled with a 60 N force at a 42-degree angle, while facing a 15 N frictional force. The calculated horizontal component of the pulling force is approximately 44.6 N. The net force acting on the box is determined by subtracting the frictional force from the horizontal component, resulting in a net force of 29.6 N. The acceleration is then calculated using Newton's second law, yielding an incorrect value due to confusion between force and mass units. The correct approach emphasizes the need to convert weight to mass for accurate calculations.
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Homework Statement


A 125 N box is pulled along the floor with a force of 60 N acting at an angle of 42 degrees to the horizontal. If the force of friction on the box is 15 N,
A. what is the acceleration of the box?
B. How much work is done to move the box over a distance of 5 m?


Homework Equations





The Attempt at a Solution


TX = Tcos0
TX = 60Ncos42
TX = 44.6N

fnet=60N - 45N
fnet = 45N

fnet= TX - Ff = ma
45N = 44.6N - 15N = (125N)(a)
45N = .237 = a
a=189.9m/s^2
 
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fnet= TX - Ff = ma
45N = 44.6N - 15N = (125N)(a)
45N = .237 = a
a=189.9m/s^2

you should only have 44.6-15N= ma
Where are you getting the 45N on the left hand side of the equation?
Also, remember that the "m" in F=ma is the MASS of the object...What are units of mass? 125N is not a mass.
 

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