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Question
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
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Solution
Voltage V = 12 V
current flowing in the circuit I = 2.5 mA = 2.5 × 10−3 A
∴ Resistance (R) = `"V"/"I"`
= `12/(2.5 xx 10^-3)`
R = `(12 xx 10^3)/25`
R = 4800 Ω
R = `4800/1000` KΩ
R = 4.8 KΩ
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