Heating Effect of Current

Why wires heat up, Joule law H equals I squared times R times t, and how fuses protect circuits. Class 7 Science with quiz.

Class 7 ScienceClass 7 / Grade 7Ages 9–12
Lesson
🔥 Heating Effect of Current
Current through a wire produces HEAT!💡Electric bulbtungsten filamentheats to 3000°C→ glows white🍞Toasternichrome wireheats up;toasts bread♨️Electric ironresistanceheating elementfor clothes

When electric current flows through a wire, it produces heat. This is because electrons moving through the wire collide with the atoms in it, transferring energy as heat. This heating effect is used in many appliances. A light bulb's tungsten filament becomes so hot — around three thousand degrees Celsius — that it glows with white light. Toasters use coiled nichrome wire. Electric irons, room heaters, and electric kettles all work on this principle.

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