If the amount of current 'I' in a coil increases four times by keeping the inductance 'L' constant, then the energy flowing in the coil becomes
Correct answer: D. 16 L I2
- A. 2 L I2
- B. 4 L I2
- C. 8 L I2
- D. 16 L I2
Explanation
The energy stored in an inductor is given by the formula E = 1/2 L I2. When the current 'I' increases by a factor of 4, the new energy stored is 1/2 L (4I)2 = 1/2 L 16I2 = 8 L I2. Thus, the energy increases by a factor of 16. Options A and B are incorrect as they do not apply the square relationship of the current increase correctly. Option C incorrectly suggests an increase by a factor of 8 rather than 16.
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About AC Through Resistor, Capacitor and Inductor
Alternating current through a resistor, capacitor and inductor involves phase relationships between voltage and current, reactance, impedance and energy transfer. A resistor keeps voltage and current in phase, while a capacitor and inductor produce opposite phase shifts, a distinction used in circuit diagrams and numerical calculations.
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