State the equation relating current to drift velocity.

I = Anev, where I is current, A is cross-sectional area, n is number density of charge carriers, e is charge per carrier, and v is mean drift velocity.

In the equation I = Anev, what does the symbol A represent?

A represents the cross-sectional area of the conductor.

In the equation I = Anev, what does the symbol n represent?

n represents the number density of charge carriers.

What characterises conductors in terms of their number density of charge carriers?

Conductors have a high number density of charge carriers.

OCR A-Level Physics A H556

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Charge and Current

Mean drift velocity

3 things to know
Papers 2 and 3

Overview

Recall questions on I = Anev, what each symbol stands for, and why drift velocity is so small.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Process

What does the equation I = Anev describe?

Key term

Define number density, and describe conductors, and metals in particular, in terms of their number density of charge carriers.

Key term

Define mean drift velocity.

Questions from this subtopic

Each one with the model answer underneath.

1
Define mean drift velocity.
Model answer
Mean drift velocity is the average velocity of charge carriers along the conductor.
2
State the equation relating current to drift velocity.
Model answer
I = Anev, where I is current, A is cross-sectional area, n is number density of charge carriers, e is charge per carrier, and v is mean drift velocity.
3
In the equation I = Anev, what does the symbol A represent?
Model answer
A represents the cross-sectional area of the conductor.
4
In the equation I = Anev, what does the symbol n represent?
Model answer
n represents the number density of charge carriers.
5
Define number density.
Model answer
Number density n is the number of charge carriers per unit volume.
6
What characterises conductors in terms of their number density of charge carriers?
Model answer
Conductors have a high number density of charge carriers.

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Mean drift velocity

Overview

What you need to know

What does the equation I = Anev describe?

Define number density, and describe conductors, and metals in particular, in terms of their number density of charge carriers.

Define mean drift velocity.

Questions from this subtopic

Define mean drift velocity.

State the equation relating current to drift velocity.

In the equation I = Anev, what does the symbol A represent?

In the equation I = Anev, what does the symbol n represent?

Define number density.

What characterises conductors in terms of their number density of charge carriers?

Other ways to work this

What is inside Levo

The 3-step method, run for you

Cram a whole paper in one sitting

Blank Blitz makes facts automatic

Build It gets the exam shape right

Test It catches misconceptions

Brain Breaks between sessions

Every question in Charge and Current, on a schedule.