Current Electricity Charging Discharging Of Capacitors Question 687
Question: The resistance of a wire is R. It is bent at the middle by $ 180{}^\circ $ and both the ends are twisted together to make a shorter wire. The resistance of the new wire is copper wire becomes three times its value at $ 0{}^\circ C $ ?
Options:
A) 2R
B) R/2
C) R/4
D) R/8
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Resistance of wire (R) $ =\rho \frac{l}{A} $ If wire is bent in the middle then $ l’=\frac{l}{2},A’=2A $
BETA
