In Physics, every physical quantity has a standard SI unit. Here are the SI units for the three most important electrical quantities tested in CBSE exams.
Resistance Unit: Ohm (Ω).
Resistivity Unit: Ohm-meter (Ω·m).
Capacitance Unit: Farad (F).
SI Unit of Electric Field: Newton per Coulomb (N/C) or Volt per meter (V/m).
SI Unit of Temperature: Kelvin (K).
The SI unit of electrical resistance is the Ohm (Ω). Definition: A conductor has a resistance of 1 Ohm when a potential difference of 1 Volt causes a current of 1 Ampere to flow through it. Formula: R = V/I (Ohm's Law).
The SI unit of resistivity (ρ) is the Ohm-meter (Ω·m). Resistivity is an intrinsic property of the material, independent of its shape. Formula: R = ρL/A → ρ = RA/L, so units = (Ω × m²)/m = Ω·m.
The SI unit of capacitance is the Farad (F). Definition: 1 Farad = 1 Coulomb per Volt. A capacitor has a capacitance of 1 Farad when 1 Coulomb of charge raises its potential by 1 Volt. Formula: C = Q/V. Note: 1 Farad is an extremely large unit. Practical capacitors use microfarad (μF) or picofarad (pF).
The SI unit of electrical resistance is the Ohm (Ω).
The SI unit of resistivity is Ohm-meter (Ω·m).
The SI unit of capacitance is the Farad (F).
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