JEE MainPhysicsUnits and MeasurementsMCQ+4 / −1
In the following ‘I’ refers to current and other symbols have their usual meaning. Choose the option that corresponds to the dimensions of electrical conductivity :
- AML 3 T 3 I2
- BM 1 L3 T3 I
- CM 1 L 3 T3 I2
- DM 1 L 3 T3 I
View written solutionFree
Correct answer: C
- Use the relation between conductivity and resistivity
Electrical conductivity is the reciprocal of resistivity :
So we first find the dimensions of resistivity.
- Dimensions of resistance
From Ohm’s law,
Now,
Dimensions of work:
Dimensions of charge:
Hence dimensions of potential difference:
Therefore,
- Dimensions of resistivity
Using
where area has dimensions and length has dimensions .
So,
- Dimensions of conductivity
Since
we get
- Match with the options
The required dimensions are:
This matches Option C.
- Verification with stored answer
Stored correct answer: C
Derived answer: C
So the derived answer agrees with the stored answer.
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