Work needed to move charge from infinity to center of sphere

In summary: Thanks for the help!In summary, the professor was trying to tell you that it would take Q*delta-V(due to q=4 pi R^2) to move a charge from infinity to the surface of the sphere.
  • #1
GTdan
39
0
Hey, I recenty took an exam and the professor asked us to turn in a corrected version of the exam based on the comments he made to us (I guess people didn't do as well as he expected). On one of the problems it asks:

How much work does it take for you to move a charge Q from infinity to the center of the sphere (all charge is located at the surface)?

I already calculated the potential from infinity to the surface of the sphere as well as the work required to create the sphere. When I originally did the problem, I did this:

W=(1/2)*Q*(Work to create sphere)

He made a comment circling that and then: Q*delta-V(due to q=4 pi R^2) from infinity to R (R=surface of sphere).

I don't really know what the professor means by that and I can't really ask him right now either. Does anyone have an idea what that comment is supposed to mean or how I should be correcting this problem?
 
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  • #2
GTdan said:
Hey, I recenty took an exam and the professor asked us to turn in a corrected version of the exam based on the comments he made to us (I guess people didn't do as well as he expected). On one of the problems it asks:
How much work does it take for you to move a charge Q from infinity to the center of the sphere (all charge is located at the surface)?
I already calculated the potential from infinity to the surface of the sphere as well as the work required to create the sphere. When I originally did the problem, I did this:
W=(1/2)*Q*(Work to create sphere)
He made a comment circling that and then: Q*delta-V(due to q=4 pi R^2) from infinity to R (R=surface of sphere).
I don't really know what the professor means by that and I can't really ask him right now either. Does anyone have an idea what that comment is supposed to mean or how I should be correcting this problem?

The potential from infinity to the surface is Delta(V). All you needed to do is multiply that by Q, and you get the work done to move the charge from infinity to the surface. This is what your Prof. was trying to tell you.

Zz.
 
  • #3
oh ok. So the potential that I originally calculated from infinity to the surface (R) time Q was what I needed. I guess I made it harder than it should have been. :redface:
 

What is the concept of work needed to move a charge from infinity to the center of a sphere?

The concept of work needed to move a charge from infinity to the center of a sphere is a measure of the energy required to move a charged particle from a point at infinity to the center of a spherical charge distribution. This is also known as the potential energy difference between infinity and the center of the sphere.

Why is it important to calculate the work needed to move a charge from infinity to the center of a sphere?

Calculating the work needed to move a charge from infinity to the center of a sphere is important in understanding the electrostatic potential energy associated with a spherical charge distribution. It also helps in understanding the forces acting on the charge and the behavior of the electric field around the sphere.

What factors affect the work needed to move a charge from infinity to the center of a sphere?

The work needed to move a charge from infinity to the center of a sphere is affected by the magnitude of the charge, the distance between the charge and the center of the sphere, and the size of the sphere. It is also affected by the presence of other charges in the surrounding environment.

How is the work needed to move a charge from infinity to the center of a sphere calculated?

The work needed to move a charge from infinity to the center of a sphere is calculated using the formula W = q(Vf - Vi), where W is the work done, q is the charge, Vf is the final potential at the center of the sphere, and Vi is the initial potential at infinity.

What are some real-life applications of the concept of work needed to move a charge from infinity to the center of a sphere?

The concept of work needed to move a charge from infinity to the center of a sphere has various real-life applications. One example is in the design of capacitors, where the work needed to move a charge from one plate to another is used to determine the capacitance. It is also relevant in understanding the behavior of electric fields in spherical conductors used in high-voltage transmission lines.

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