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The number of free electrons per 100 mm ...

The number of free electrons per 100 mm of ordinary copper wire is `2xx10^(21)`. The average drift speed of electorn is `0.25 mm//s`. What is the current flowing?

A

0.8A

B

8A

C

80A

D

5A

Text Solution

Verified by Experts

The correct Answer is:
B
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MOTION-CURRENT ELECTRICITY-EXERCISE -2 (OBJECTIVE PROBLEMS NEET)
  1. Which of the following is scalar :–

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  2. The current conduction in a discharged tube is due to

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  3. The number of free electrons per 100 mm of ordinary copper wire is 2xx...

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  4. The length of a given cylindrical wire is increased by 100%. Due to th...

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  5. Three copper wires of length and cross-sectional areas are (L,A)(2L,(A...

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  6. When a piece of aliminium wire of finite length is drawn through a ser...

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  7. The resistivity of a wire depends on its

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  8. The conductivity of a super conductor is

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  9. A copper wire iis stretched to make it 0.1% longer. What is the percen...

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  10. A metal wire of resistance R is cut into three equal pieces that are t...

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  11. Masses of three wires of same metal are in the ratio 1:2:3 and their l...

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  12. As the temperature of a metallic resistor is increased,the product of ...

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  13. A bullet of mass 2 gm is having a charge of 2 muc. Through what potent...

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  14. What will be the equivalent resistance between the A and D ?

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  15. In the arrangement of resistances shown in the circuit. The potential...

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  16. Express which of the following set ups can be used to verify ohm's l...

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  17. The resistance across P and Q in the given figure is

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  18. Electromotive force of a cell is basically a

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  19. A battery of e.m.f. 10 V and internal resistance 0.5 ohm is connected ...

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  20. The resistance of the circuit between A and B is :

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