Current Electricity Charging Discharging Of Capacitors Question 406
Question: The resistance of a 5 cm long wire is 10 W. It is uniformly stretched so that its length becomes 20 cm. The resistance of the wire is
[MH CET 2002]
Options:
A) 160 W
B) 80 W
C) 40 W
D) 20 W
Show Answer
Answer:
Correct Answer: A
Solution:
$ \frac{R _{1}}{R _{2}}={{( \frac{l _{1}}{l _{2}} )}^{2}} $
$ \Rightarrow ,\frac{10}{R _{2}}={{( \frac{5}{20} )}^{2}}=\frac{1}{16}=R _{2}=160\Omega $ .
BETA
