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Write down an expression for the resistance of a metallic wire in terms of the resistivity.

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Question

Write down an expression for the resistance of a metallic wire in terms of the resistivity.

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Solution

 Length of the cable wire = l 

Area of cross-section = A
Resistivity of the aluminium cable wire = `rho` 
 
Resistance of the wire = R

Then,  `R=l/A` 

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Chapter 4: Electricity - Exercise 4 [Page 214]

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Lakhmir Singh Physics Part 1 [English] Class 10
Chapter 4 Electricity
Exercise 4 | Q 15. (a) | Page 214

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