A copper wire of radius \(1\) mm contains \(10^{22}\) free electrons per cubic metre. The drift velocity for free electrons when \(10\) A current flows through the wire will be:
(Given, charge on electron = \(1.6\times10^{-19}\) C)
1. \(\frac{6.25\times10^4}{\pi}\) m/s
2. \(\frac{6.25}{\pi}\times10^3\) m/s
3. \(\frac{6.25}{\pi}\) m/s
4. \(\frac{6.25\times10^5}{\pi}\) m/s
Subtopic:  Current & Current Density |
 71%
From NCERT
NEET - 2023
Please attempt this question first.
Hints
Please attempt this question first.

When no current is passed through a conductor,

a. the free electrons do not move.
b. the average speed of a free electron over a large period of time is zero.
c. the average velocity of a free electron over a large period of time is zero.
d. the average of the velocities of all the free electrons at an instant is zero.

Choose the correct option: 
1. (a) only 
2. (b), (c) 
3. (c), (d) 
4. (a), (d) 

Subtopic:  Current & Current Density |
 57%
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

Across a metallic conductor of non-uniform cross-section, a constant potential difference is applied. The quantity which remains constant along the conductor is:
1. current density 2. current
3. drift velocity 4. electric field
Subtopic:  Current & Current Density |
 59%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

advertisementadvertisement

A copper wire of length \(10\) m and radius \(\left({10^{-2}/\sqrt{\pi}}\right)\) m has an electrical resistance of \(10~\Omega.\) The current density in the wire for an electric field strength of \(10\) (V/m) is: 
1. \(10^{5}\) A/m2
2. \(10^{4}\) A/m2
3. \(10^{6}\) A/m2
4. \(10^{-5}\) A/m2
Subtopic:  Current & Current Density |
 66%
From NCERT
NEET - 2022
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

A charged particle having drift velocity of \(7.5\times10^{-4}~\text{ms}^{-1}\) in an electric field of \(3\times10^{-10}~\text{Vm}^{-1}\), has mobility of: 
1. \(2.5\times 10^{6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
2. \(2.5\times 10^{-6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
3. \(2.25\times 10^{-15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
4. \(2.25\times 10^{15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)

Subtopic:  Current & Current Density |
 82%
From NCERT
NEET - 2020
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh