Define Drift speed. Also we know that the drift speed of a steady current carrying conductor is about 1mm/s. Then how we observe lightening fast speed of current in a typical circuit?
Asked by Akshit Wahi | 12th Sep, 2011, 12:00: AM
Expert Answer:
In a conductor, the electrons undergo frequent collisions with the ions of the material. Hence, the direction of the electrons undergoes a random change. See figure below, the net effect is that in addition to the random motion of the electrons, there is also a very slow net motion or drift of the electrons. This drift or flow with a constant velocity (in a direction opposite to
) is called the drift velocity VD.

The drift velocity of the electrons Vd is (using E = V / l)

In a circuit, when potential difference is applied, the electrons gets attracted towards the positive terminal and acquire a faster speed.
In a conductor, the electrons undergo frequent collisions with the ions of the material. Hence, the direction of the electrons undergoes a random change. See figure below, the net effect is that in addition to the random motion of the electrons, there is also a very slow net motion or drift of the electrons. This drift or flow with a constant velocity (in a direction opposite to
) is called the drift velocity VD.

The drift velocity of the electrons Vd is (using E = V / l)
In a circuit, when potential difference is applied, the electrons gets attracted towards the positive terminal and acquire a faster speed.
Answered by | 13th Sep, 2011, 10:34: AM
Related Videos
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Sign Up
Verify mobile number
Enter the OTP sent to your number
Change