Question

In the given circuit, when battery supplies 9 V the resistance of the given resistor is R. If the strength of the battery is increases to 18 V resitance of the circuit becomes $R^{{}^{\prime }}$. Calculate the ratio $\frac{R^{{}^{\prime }}}{R}$.

• A. 1
• B. 2
• C. $\frac{1}{2}$
• D. 0

Answer 1

The correct option is A 1

Resistance of a given resistor only changes when the dimension of the resistor or temperature around it is changed.
Since dimension and temperature remains same in this question, resistance would remain same even though voltage is increased.
Thus
$\frac{R^{{}^{\prime }}}{R}=1$