A wire of length 100 cm is connected to a cell of emf 2 V and negligible internal resistance. The resistance of the wire is 3 , the additional resistance required to produce a potential difference of 1 mV / cm is

Step-by-step solution

Resistance per unit length of wire x= 3 100 =3 10⁻² ~cm ⁻¹ Equivalent length of wire l^ = R+3 3 10⁻² R being additional resistance array rlrl & & E k & = R+3 3 10⁻² & 2 1 10⁻³ & = R+3 3 10⁻² & R & =57 array