Questions regarding generalized work equation

In summary, the work equation is a generalized equation that describes the energy required to displace an object with a force in the direction of displacement. It can be represented as W = \int \vec{F} \cdot {d}\vec{x} and can also have bounds in multiple dimensions. This equation applies to both conservative and non-conservative forces, with the latter being a negative change in potential energy. Work is not energy, but rather causes a change in energy and can be calculated by finding the net work or the change in potential energy and kinetic energy.
  • #1
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1
Hello, I am trying to generalize the work equation and understand the very definition of it. From what I understand, Work is the energy required to displace an object with a force in the direction of the displacement. (also the change in kinetic energy but I'm not going to worry about that yet)
[tex] W = \int \vec{F} \cdot {d}\vec{x} [/tex] This equation makes sense to me. If I were to add bounds to the integral, would they be in 3-D if the displacement and force is in 3-D?
Otherwise
[tex] W = \int_{x_i}^{x_f} {F_x} {dx} + \int_{y_i}^{y_f} {F_y} {dy} + \int_{z_i}^{z_f} {F_z} {dz}[/tex]
This method would get the work with calculus I know of. Is it possible to make bounds in multiple dimensions? If so, how would one solve them? Thank you!

edit: Oh one more question: This equation describes non-conservative work, right? What would describe conservative work? Just this? [tex] W = \vec{F} \cdot \vec {d} [/tex]
 
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  • #2
It describes a force that varies with position, unlike your second formula.

The generalized work integral is a line integral, which you'll be able to solve in the general case after you've taken multvariable calculus. It essentially let's you integrate over whatever path you need to integrate over for the problem.
 
  • #3
The generalized equation for
Work = [itex]\int F.ds[/itex] applies to both conservative and non conservative forces. For conservative forces , the work done is equal to [itex] - \Delta PE[/itex] . For work done by conservative forces like springs in particular, performing the work integral where F = -kx yields W = -1/2(kx^2) when the spring stretches from rest to x. This is the negative of the change in its PE. Work is not energy, it causes a change in energy, which might be positive or negative or zero. Net work is change in KE, while non conservative work is change in PE plus change in KE. You can also regard non conservative work as the negative of the change in thermal/other energy.
 

What is the generalized work equation?

The generalized work equation is a mathematical representation of the relationship between work, force, and displacement. It states that the work done on an object is equal to the force applied multiplied by the displacement of the object in the direction of the force.

What are the units of measurement for each variable in the generalized work equation?

The units for work are joules (J), force is measured in newtons (N), and displacement is measured in meters (m). Therefore, the units for the generalized work equation are joules (J) = newtons (N) x meters (m).

Can the generalized work equation be applied to all types of work?

Yes, the generalized work equation can be applied to all types of work, including mechanical, electrical, and gravitational work. As long as there is a force acting on an object causing it to move a certain distance, the generalized work equation can be used to calculate the work done.

What is the significance of the angle between the force and displacement in the generalized work equation?

The angle between the force and displacement is important in the generalized work equation because it determines the direction of the work done. If the force and displacement are in the same direction, the work done is positive, but if they are in opposite directions, the work done is negative.

Is the generalized work equation a universal law in physics?

No, the generalized work equation is not a universal law in physics, but rather a mathematical representation of the relationship between work, force, and displacement. It is derived from other fundamental laws such as Newton's laws of motion and the principle of conservation of energy.

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