This comprehensive guide provides a curated physics equation sheet for 2025, covering key concepts across various branches of physics. While no single sheet can encompass every equation, this resource aims to be a valuable tool for students preparing for exams, tackling problem sets, or simply reviewing fundamental principles. Remember, understanding the underlying concepts is as crucial as memorizing the equations themselves.
Mechanics
Kinematics (Motion in One and Two Dimensions)
- Displacement: Δx = xf - xi
- Average Velocity: vavg = Δx/Δt
- Instantaneous Velocity: v = dx/dt
- Average Acceleration: aavg = Δv/Δt
- Instantaneous Acceleration: a = dv/dt
- Uniformly Accelerated Motion:
- vf = vi + at
- Δx = vit + (1/2)at²
- vf² = vi² + 2aΔx
Dynamics (Forces and Newton's Laws)
- Newton's Second Law: ΣF = ma
- Weight: W = mg
- Friction (Kinetic): fk = μkN
- Friction (Static): fs ≤ μsN
- Gravitational Force: Fg = Gm1m2/r²
Work, Energy, and Power
- Work: W = Fd cosθ
- Kinetic Energy: KE = (1/2)mv²
- Potential Energy (Gravitational): PEg = mgh
- Potential Energy (Elastic): PEs = (1/2)kx²
- Power: P = W/t = Fv
Rotational Motion
- Angular Displacement: θ
- Angular Velocity: ω = dθ/dt
- Angular Acceleration: α = dω/dt
- Relationship between Linear and Angular Quantities: v = rω, at = rα, ac = v²/r = ω²r
Thermodynamics
Heat and Temperature
- Heat Transfer: Q = mcΔT
- Specific Heat Capacity: c
- Latent Heat: Q = mL
Laws of Thermodynamics
- First Law: ΔU = Q - W
- Second Law: (various formulations, including the Clausius and Kelvin statements)
Electromagnetism
Electric Fields and Forces
- Coulomb's Law: Fe = kq1q2/r²
- Electric Field: E = Fe/q
- Electric Potential: V = kq/r
Electric Circuits
- Ohm's Law: V = IR
- Power in a Circuit: P = IV = I²R = V²/R
- Series Resistance: Rtotal = R1 + R2 + ...
- Parallel Resistance: 1/Rtotal = 1/R1 + 1/R2 + ...
Magnetism
- Magnetic Force on a Moving Charge: FB = qvBsinθ
- Magnetic Force on a Current-Carrying Wire: FB = ILBsinθ
Waves and Optics
Wave Properties
- Wave Speed: v = fλ
- Wave Interference (Constructive): path difference = nλ
- Wave Interference (Destructive): path difference = (n + 1/2)λ
Optics
- Index of Refraction: n = c/v
- Snell's Law: n1sinθ1 = n2sinθ2
Modern Physics (Introductory)
- Photoelectric Effect: KEmax = hf - φ
- Einstein's Mass-Energy Equivalence: E = mc²
Disclaimer: This equation sheet is intended as a quick reference and may not be exhaustive. Always consult your textbook and lecture notes for a complete understanding of the concepts and their applications. This information is for educational purposes only and should not be considered professional advice.
