Find Electron Current Through Iron Wire

In summary, the question asks what electron current is driven through a 1.4-mm-diameter iron wire by a 0.070 V/m electric field, given a mean time between collisions in iron of 5.2×10^−15s, A=1.5*10^-6 m^2, and ne=8.5*10^28 m^-3. The author attempted to solve for drift speed using ie = neAVd, but was unsure of how to find the drift speed. The answer was eventually found to be 8.4*10^18 electrons/s using information from the Hyperphysics website.
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Homework Statement


What electron current is driven through a 1.4-mm-diameter iron wire by a 0.070 V/m electric field? The mean time between collisions in iron is 5.2×10^−15s .
A=1.5*10^-6 m^2
ne=8.5*10^28 m^-3

Homework Equations


I know I need to use ie = neAVd, but I'm having trouble finding the drift speed.

The Attempt at a Solution


I set up ie = neAVd , as I currently know both ne and A, but the vd value is what's throwing me off. I multiplied the collision speed by the electric field strenght and got vd=3.64*10^-16m/s, which led to a final answer of ie=4.6*10^7 electrons/s. However, I was wrong and the answer is 8.4*10^18 electrons/s.
 
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1. How can I find the electron current through an iron wire?

The electron current through an iron wire can be determined by using Ohm's Law, which states that current (I) is equal to the voltage (V) divided by the resistance (R). Therefore, to find the electron current through an iron wire, you need to measure the voltage and resistance of the wire.

2. What is the resistance of iron wire and how does it affect the electron current?

The resistance of iron wire is dependent on its length, cross-sectional area, and temperature. The longer the wire, the higher the resistance. The smaller the cross-sectional area, the higher the resistance. Higher temperatures also increase the resistance of iron wire. Resistance directly affects the electron current, as stated in Ohm's Law. Higher resistance means lower current.

3. Can the electron current through an iron wire be changed?

Yes, the electron current through an iron wire can be changed by altering the voltage or resistance. Increasing the voltage will increase the current, while increasing the resistance will decrease the current. Additionally, changing the temperature of the wire can also affect its resistance and, therefore, the electron current through it.

4. What are the units of electron current and how is it measured?

The unit of electron current is ampere (A), which is a measure of the amount of charge passing through a point in one second. Electron current can be measured using an ammeter, which is a device that measures the flow of electric current in a circuit.

5. Is there a difference between electron current and conventional current?

Yes, there is a difference between electron current and conventional current. Electron current describes the flow of negatively charged electrons, while conventional current describes the flow of positively charged particles (such as protons) in the opposite direction. In most cases, the two currents have the same magnitude, but they flow in opposite directions.

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