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Question
A resistor of resistance R is connected to an ideal battery. If the value of R is decreased, the power dissipated in the resistor will ______________ .
Options
increase
decrease
remain unchanged
Solution
increase
As the resistance is connected to an ideal battery, it provides a constant potential difference across the two terminals. The internal resistance of the battery is also zero.
The power dissipated in the resistor,
P = \[\frac{V^2}{R}\]
V is constant; hence V \[\propto \frac{1}{R^{}}\]
Thus, if the value of the resistance is decreased, the power dissipated in the resistor will increase.
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