Curious about Work done by Gravitational force

In summary, the relationship between gravity and cosine, rather than sine, in a free body diagram may depend on how the angle is defined and the location of the "corner" of the right angle triangle with respect to the leg representing mgd.
  • #1
Selectron09
20
3

Homework Statement


I don’t understand why this would relate to cosine and not sine, if gravity is often assiciated in the up and down part of a free body diagram.

Homework Equations

Wg=mgdcos(theta)[/B]

The Attempt at a Solution


Is it because it would depend on your reference frame?
 
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  • #2
Hi Selectron09,

Welcome to Physics Forums.

Selectron09 said:
Is it because it would depend on your reference frame?
Not really. It depends upon how the angle in question is defined; which "corner" of the right angle triangle is located with respect to the leg that represents your ##mgd##.

upload_2018-10-27_12-37-55.png
 

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  • #3
Oh! Ok that clears things up a lot. Thankyou.
 

1. What is work done by gravitational force?

The work done by gravitational force is the amount of energy transferred when an object moves against the force of gravity. It is calculated by multiplying the force of gravity by the distance an object moves in the direction of the force.

2. How is work done by gravitational force related to potential energy?

Work done by gravitational force is directly related to potential energy. As an object moves against the force of gravity, it gains potential energy. This potential energy can then be converted into kinetic energy as the object falls back towards the ground.

3. Can work be done by gravitational force on a stationary object?

No, work can only be done when there is a displacement of the object. If an object is stationary, there is no displacement and therefore no work is being done by gravitational force.

4. How does the mass of an object affect the work done by gravitational force?

The mass of an object does not directly affect the work done by gravitational force. The work done is dependent on the distance an object moves against the force of gravity, not its mass.

5. Is the work done by gravitational force the same for all objects?

No, the work done by gravitational force will vary depending on the mass and distance an object moves. For example, a heavier object will require more work to be moved against gravity than a lighter object. Additionally, the work done will also vary depending on the strength of the gravitational force, which can vary depending on the location and mass of the objects involved.

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