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A cross–sectional area of a copper wire ...

A cross–sectional area of a copper wire is `3xx10^(–6) m^2`. The current of 4.2 amp. is flowing through it. The current density in `"amp"//m^2` through the wire is –

A

`1.4xx10^3`

B

`1.4xx10^4`

C

`1.4xx10^5`

D

`1.4xx10^6`

Text Solution

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The correct Answer is:
D
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MOTION-CURRENT ELECTRICITY-EXERCISE -1 (OBJECTIVE PROBLEMS NEET)
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  3. A cross–sectional area of a copper wire is 3xx10^(–6) m^2. The current...

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  4. Two wires each of radius of cross section r but of different materials...

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  6. An insulating pipe of cross-section area A contains an electrolyte whi...

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  8. In the presence of an applied electric field (vecE) in a metallic con...

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  9. A wire has non-uniform cross-section as shown in fig. steady current f...

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  10. Specific resistance of a wire depends on its

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  18. A conductor with rectangular cross section has dimensions (axx2axx4a) ...

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