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The variation of current 'I' with the voltage applied 'V' across the conductor is given by V = R sin(I), where R is the resistance of the conductor and I ∈ [0,\(\frac{\pi}{2}\)]. The conductor follow Ohm's law for all values of 'I' that are

The variation of current 'I' with the voltage applied 'V' across the conductor is given by V = R sin(I), where R is the resistance of the conductor and I ∈ [0,\(\frac{\pi}{2}\)]. The conductor follow Ohm's law for all values of 'I' that are Correct Answer very small

CONCEPT:

​Ohm's law:

  • A conductor through which a current I is flowing and let V be the potential difference between the ends of the conductor. Then Ohm’s law states that

⇒ V ∝ I

⇒ V = IR

where R is called the resistance of the conductor. Resistance depends on the shape, size, and material of the conductor.

Limitations of Ohm's law:

  • Ohm’s law is valid over a large class of materials.
  • There do exist materials and devices used in electric circuits where the proportionality of V and I does not hold. 

The deviations in occurring are one or more of the following types:

  • V is not to be proportional to I for some range of V or I

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  • The relation between V and I depends on the sign of V. 
    • Reversing the direction of V keeping its magnitude fixed does not produce a current of the same magnitude as I in the opposite direction.

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  • The relation between V and I is not unique
    • There is more than one value of V for the same current I 

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EXPLANATION:

Given V = R sin(I)

Ohm's law:

  • A conductor through which a current I is flowing and let V be the potential difference between the ends of the conductor. Then Ohm’s law states that

⇒ V ∝ I

⇒ V = RI

where R is called the resistance of the conductor. Resistance depends on the shape, size, and material of the conductor.

  • For sin θ, if θ is very small, 

⇒ sinθ ≈  θ

  • Similarly, in V = R sin(I), if I is very small, 

⇒ sin(I) ≈  I

⇒ V = R sin(I) ≈ RI

  • ​Therefore option 3 is correct. 

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