Introduction
Ohm's law, resistance, series/parallel circuits, electric power, and heating effect.
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Circuits and Power
V=IR (Ohm's law). R=rho.L/A. Series: Rs=R1+R2 (same current). Parallel: 1/Rp=1/R1+1/R2 (same voltage). Power P=VI=I^2R=V^2/R. Energy E=Pt. 1kWh=3.6x10^6J. Heating H=I^2Rt.
Key Points
- •V=IR; R=rho.L/A
- •Series: same current; Parallel: same voltage
- •P=VI=I^2R=V^2/R
- •1kWh=3.6x10^6J
- •Fuse protects against overcurrent
Quick Summary
- ✓V=IR; Series: Rs=R1+R2; Parallel: 1/Rp=1/R1+1/R2
- ✓P=VI; E=Pt; H=I^2Rt
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Key Formulas
V=IR; R=rho.L/A
Series: Rs=R1+R2+R3; Parallel: 1/Rp=1/R1+1/R2+1/R3
P=VI=I^2R=V^2/R; H=I^2Rt; 1kWh=3.6x10^6J
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