HELP! Change in GPE and Work Done (1 Viewer)

[heyhsc]

I don't know how to explain the relationship..
the dotpoint is Explain that a change in GPE is related to work done

Please help!

 

[kiinto]

When an object is moved to a higher orbit, it gains energy because work is done to move it to that new orbit and due to the Law of Conservation of Energy this cannot be destroyed. It is converted to Gravitational potential energy, which is the amount of energy the object would regain (in kinetic energy) if it were to fall.

 

[Amundies]

When an object is raised while in a gravitational field, kinetic energy must be used in order to raise the amount of GPE. Since work done = change in KE, work must be done to raise the object. Similarly, when an object falls in a gravitational field, the gravitational field exerts a force on the object converting some of the GPE into KE. Once again, since work done = change in KE, work is still being done.

 

[heyhsc]

thanks guys!

Gravitational potential energy is the energy required of an object to move in a gravitational field from a point of zero potential. Since work done is the change in kinetic energy, work is done to move an object in a gravitational field. Therefore, GPE is related to work done.

does this sound right?

 

[Amundies]

That sounds ok to me, probably need to get someone else to make sure it's fine though.

 

[kiinto]

thanks guys!

Gravitational potential energy is the energy required of an object to move in a gravitational field from a point of zero potential. Since work done is the change in kinetic energy, work is done to move an object in a gravitational field. Therefore, GPE is related to work done.

does this sound right?

I think you've got it, but your wording is a but iffy. Gravitational potential energy isn't energy required for something to happen, it is the potential for energy to be released (as Ek). However, it is equal to the work required to move an object from a point of zero Ep to another position.

That's my understanding of it.

 

[heyhsc]

hi kiinto, do u think this is alright?

Gravitational potential energy is the potential energy of a mass due to its position within a gravitational field, to be released as kinetic energy. Since work done is the change in kinetic energy, work is done to move an object in a gravitational field. Therefore, GPE is related to work done.

i know gpe is work done but i cant explain their relationship

 

[RishBonjour]

hi kiinto, do u think this is alright?

Gravitational potential energy is the potential energy of a mass due to its position within a gravitational field, to be released as kinetic energy. Since work done is the change in kinetic energy, work is done to move an object in a gravitational field. Therefore, GPE is related to work done.

i know gpe is work done but i cant explain their relationship

Bolded part should be enough.
Say an object is at a certain position in the earth's gravitational field and has a certain value of GPE. Now, for its GPE to change, there has to be a change in its position in the gravitational field right? For this change in position to occur work must be done on that object, hence a change in GPE is related to work done. Also, say, you do work on an object AWAY from the earth's gravitational field, this work you just did cannot be destroyed (conservation of energy) but rather is transferred into increased GPE for that object.

Thats basically it.

 

[kiinto]

You got it. Just avoid saying Ep is W, rather, say Ep is equal to W. Same goes for W and Ek, or Ep and Ek.

 

[heyhsc]

thank you so much!! i get it!