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Assertion : Current I is flowing through...


Assertion : Current `I` is flowing through a cylindrical wire of non-uniform cross-section as shown. Section of wire near `A` will be more heated compared to the section near B.
Reason : Current density near `A` is more.

A

If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.

B

If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

C

If Assertion is true, but the Reason is false.

D

If Assertion is false but the Reason is true.

Text Solution

Verified by Experts

The correct Answer is:
B
`R=(rhol)/Aor R/l=` resistance per unit length `=rho/Aprop1/A`
Near `A`, areas of cross section is less. Therefore, resistance per unit length will be more. Hence from the equation `H=i^2Rt`, heat generation near A will be more.
Current density `J=i/A` or `Jprop1/A` (as i is same)`
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