What is the amount of work done in moving the box from the bottom to t

AI Thread Summary
To calculate the work done in moving a 160 Newton box up a 10-meter frictionless incline at a 30° angle, one must consider the conservation of energy. Since the box moves at a constant speed, the work done is equal to the change in gravitational potential energy. The height gained can be determined using trigonometry, specifically the sine of the incline angle. The discussion highlights confusion around the variables in the initial equation and emphasizes the need to focus on the energy change rather than kinematic equations. Ultimately, the work done is directly related to the energy change as the box moves from the bottom to the top of the incline.
TheLetterDex
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Homework Statement



A 160 Newton box sits on a 10 meter long frictionless plane inclined at an angle of 30° to the horizontal as shown. Force (F) applied to a rope attached to the box causes the box to move with a constant speed up the incline.

Calculate the amount of work done in moving the box from the bottom to the top of the inclined plane.
_____ J


The Attempt at a Solution


So far i come up with h=u*t-0.5*g*t^2, but now sure where to go
 
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TheLetterDex said:
So far i come up with h=u*t-0.5*g*t^2, but now sure where to go

What is "h" and what is "u"?


There is a simple way to do this based on conservation of energy. None of the energy is lost to friction.
 
Nathanael said:
What is "h" and what is "u"?


There is a simple way to do this based on conservation of energy. None of the energy is lost to friction.

Yeah I am not sure where i was going with this very confused with the question
 
TheLetterDex said:
Yeah I am not sure where i was going with this very confused with the question

The problem says to find the work done.

Work is (or "causes") a change in energy.

Does the box change it's energy at all from the bottom of the incline to the top?
 
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