Electron drift speed, Current, and Electric field in hollow wire?

In summary, a hollow copper wire with a current of 2.50 amps and dimensions of 1.4 mm (inner diameter) and 2.6 mm (outer diameter) has an electron drift speed and current density. The electron density of copper is 8.5x1028 m-3 and its conductivity is 6.0x107 (ohm m)-1. Using the equations I=neeVdA and J=I/A, we can calculate the electron drift speed and current density. The electric field can be found using the equation J=σE. It is important to note that when finding the area, it must be done separately for each section and then subtracted.
  • #1
conov3
34
0

Homework Statement



A hollow copper wire with an inner diameter of 1.4 mm and an outer diameter of 2.6 mm carries a current of 2.50 amps. Copper has an electron density of 8.5x1028 m-3 and a conductivity of 6.0x107 (ohm m)-1.
a. What is the electron drift speed in the wire?
b. What is the current density in the wire?
c. What is the electric field in the wire?

Homework Equations



a) I=neeVdA
b)J=I/A
c)J=σE

The Attempt at a Solution


I believe I have the correct answers but was just curious if someone could double check me!
Thank you!
 

Attachments

  • phys3.pdf
    185.9 KB · Views: 1,147
Last edited:
Physics news on Phys.org
  • #2
Bra, your algebra is wrong. When you find the area, do it for each section separably and subtract them from each other you will see your error. X^2-Y^2 does not equal (X-Y)^2
 

Related to Electron drift speed, Current, and Electric field in hollow wire?

1. What is electron drift speed?

The electron drift speed is the average velocity at which electrons move through a conductor when an electric field is applied. It is typically on the order of millimeters per second, but can vary depending on the material and conditions.

2. How is current related to electron drift speed?

Current is directly proportional to the electron drift speed. This means that as the electron drift speed increases, so does the current, and vice versa. However, it's important to note that other factors such as the number of electrons and the cross-sectional area of the conductor also affect the current.

3. What is the relationship between electric field and electron drift speed?

The electric field is what causes the electrons to drift in the first place. As the strength of the electric field increases, so does the electron drift speed. This is because a stronger electric field exerts a larger force on the electrons, causing them to move faster.

4. How does the shape of a hollow wire affect electron drift speed and current?

The shape of a hollow wire can affect the electron drift speed and current in a few ways. A larger cross-sectional area will allow more electrons to flow, resulting in a higher current. Additionally, a shorter length will decrease the resistance, allowing more electrons to flow and increasing the current. However, the shape of the wire does not have a direct effect on the electron drift speed, as it is primarily determined by the electric field.

5. How does temperature affect electron drift speed and current in a hollow wire?

Temperature can impact electron drift speed and current in a few ways. An increase in temperature can lead to an increase in collisions between electrons and atoms, which can slow down the electron drift speed. This can also increase the resistance of the wire, leading to a decrease in current. However, different materials have different temperature dependencies, so the exact effect on electron drift speed and current may vary.

Similar threads

Finding the drift speed of a conduction electrons
Replies
13
Views
2K
Find the drift speed of electrons in a wire
Replies
2
Views
1K
Find Electron Current Through Iron Wire
Replies
1
Views
10K
Exploring the Drift Speed of Electrons in Conductors
Replies
6
Views
2K
Long distance electrical transmission efficiency
Replies
2
Views
1K
A copper wire contains 3.0 *10 ^ 22 number of charges on 1 meter wire
Replies
8
Views
1K
Change in the Electric Field Due to a Copper Wire Being Inserted
Replies
14
Views
4K
How Fast Do Electrons Travel in a Copper Wire?
Replies
4
Views
5K
How can an increase in area cause a decrease in drift speed?
Replies
6
Views
4K
How Do You Calculate Electric Energy Density Near a Copper Wire?
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top