Current Electricity Charging Discharging Of Capacitors Question 280
Question: 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 W. The additional resistance required to produce a potential drop of 1 milli volt per cm is
[Kerala PET 2002]
Options:
A) 60 W
B) 47 W
C) 57 W
D) 35 W
Show Answer
Answer:
Correct Answer: C
Solution:
Potential gradient $ x=\frac{e}{(R+R _{h}+r)}.\frac{R}{L} $
$ \Rightarrow \frac{{{10}^{-3}}}{{{10}^{-2}}}=\frac{2}{(3+R _{h}+0)}\times \frac{3}{1}\Rightarrow R _{h}=57\Omega $ .
BETA
