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Two bars of equal resistivity rho and ra...

Two bars of equal resistivity `rho` and radius 'r' and '2r' are kept in contact as show. An electric current is passed through the bars. Which one of the following is correct ?

A

Heat produced in bar BC is 4 times the heat produced in bar AB

B

Electric field in both halves is equal

C

Current density across AB is double that of across BC

D

Potential difference across AB is 4 times that of across BC

Text Solution

Verified by Experts

The correct Answer is:
A
current flowing through both the bars is equal now the heat produced is given by
`H=I^(2)Rt`
or `HalphaR`
`H_(BC)=4H_(AB)`
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