The heating effect of electric current is described by: MCQ with Answer and Explanation

The heating effect of electric current is described by:
A. Ohm's law
B. Joule's law
C. Lenz's law
D. Faraday's law
Answer: Option B
Solution (By JKSSB Mock Tests)
Joule's law states that heat produced H = I²Rt, where I is current, R resistance, t time. This quantifies electrical energy converted to thermal energy in resistors. Ohm's law relates V, I, R; Faraday's and Lenz's laws concern electromagnetic induction. Memory aid: 'Joule heating ∝ I²R'. This definition-based question tests knowledge of fundamental laws in electricity, commonly examined in competitive exams. Applications include electric heaters, fuses, and incandescent bulbs. Always distinguish Joule's law (heating) from power formulas (P=VI=I²R=V²/R).

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