Class 12 Physics Formulas Handbook (Chapter-wise)

Every key formula and result from the Class 12 Physics NCERT syllabus, organised by chapter, in one place. Cross-linked to our full Chapter-wise Solutions. More chapters will be appended here as their Solutions are published.

Class 12 Physics Formulas Handbook

Chapter 1: Electric Charges and Fields

• Coulomb’s law: F = kq₁q₂/r², k=1/(4πε₀)≈9×10⁹ N·m²/C²
• Electric field: E = kq/r²
• Dipole moment: p = q×2a; axial field ≈ 2kp/r³; equatorial field ≈ kp/r³
• Torque on dipole: τ = pE sinθ; potential energy U = −pE cosθ
• Flux: φ = EA cosθ
• Gauss’s law: φ = Q_enclosed/ε₀
• Infinite line charge: E = λ/(2πε₀r)
• Infinite sheet: E = σ/(2ε₀); between opposite charged plates: E = σ/ε₀
• Charged spherical shell: outside E=kQ/r², inside E=0
• See full Chapter 1 Solutions

Written by Satish

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