student144
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work done is energy transfer but it's also the energy transfer that allows a force to move an object by a distance
so if I apply a force on a spring how is work done if the spring isn't moving a distance (it changes shape)
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Joinedup
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(Original post by student144)
work done is energy transfer but it's also the energy transfer that allows a force to move an object by a distance
so if I apply a force on a spring how is work done if the spring isn't moving a distance (it changes shape)
The direction of the force is parallel to the direction of the displacement in work done calculations.

If you apply a force to a spring and it changes shape without any displacement parallel to the force I don't see why it wasn't already in the final shape to start with tbh. Have you got any examples?
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M_ichael
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As it's energy transferred, you transfer energy from the chemical energy of your hand to the elastic potential energy store of the spring, causing it to expand.
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Eimmanuel
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(Original post by student144)
work done is energy transfer but it's also the energy transfer that allows a force to move an object by a distance
so if I apply a force on a spring how is work done if the spring isn't moving a distance (it changes shape)
I think the fundamental issue is in regards to the definition of work.
As far as I know that there are at least two definitions of work. One of them is restricted to particle model or rigid objects. I think you are given this definition based on “the energy transfer that allows a force to move an object by a distance” and should not be applied to objects such as spring which is a deformable object.

The more general definition of work can be applied to the spring which can be stated as follow:
Qualitative version
Work is done when a force moves its point of application along the direction of its line of action.

Quantitative version
The work W done on a system by an agent exerting a constant force on the system is the product of the magnitude F of the force, the magnitude Δs of the displacement of the point of application of the force, and cos θ, where θ is the angle between the force and displacement vectors:
W = F Δs cos θ
The displacement in this definition of work is that of the point of application of the force NOT the displacement of the object.
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