Find the angle to the horizonal using the given information.

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To find the angle at which the man pulls the rope, the key is to use the mass of the crate and the acceleration rather than focusing on work or velocity. The discussion emphasizes applying Newton's second law (F=ma) to break the pulling force into horizontal and vertical components. The user expresses confusion over the concepts of work and energy, realizing that they need to approach the problem differently. Acknowledging the oversight, they appreciate the guidance provided. Understanding the correct application of force components is crucial for solving the problem effectively.
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Homework Statement


A man pulls a wooden crate across a floor by a rope.
Mass of the crate = 15Kg
Force the man pulls with = 65N
Acceleration of the box = 20 M/s²

What is the angle to the horizontal at which the man pulls the rope.


Homework Equations



W = Fa Δd cosΘ
W = ½mv²
(think)


The Attempt at a Solution



I clearly don't understand this, but at first I figured I would use W = Fa Δd cosΘ and just rearrange the equation, then I realized, I don't have Work, figured I would find that using
W = ½mv². Then I realized I don't have Velocity, I can't find velocity without distance and I can't find distance without time.
I'm lost.
 
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Don't use work, and don't use velocity. Use mass and acceleration. Use F=ma. Split F into horizontal and vertical components.
 
Dick said:
Don't use work, and don't use velocity. Use mass and acceleration. Use F=ma. Split F into horizontal and vertical components.
Bah! I feel so silly, this whole unit is on energy and work I became a little closed minded and forgot there were other formulas I could use.
Thank you !
=)
 
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