Essential Physics Equations and Formulas for Students

Motion and Forces

• Distance: distance = speed × time
• Acceleration: a = (v - u) / t (a = acceleration, v = final velocity, u = starting velocity, t = time)
• Force: F = m × a (Force = mass × acceleration)
• Weight: W = m × g (g = gravitational field strength; on Earth, g = 9.8 N/kg)
• Momentum: p = m × v (p = momentum)
• Motion (Time Unknown): v² - u² = 2 × a × x
• Force from Change in Momentum: F = (m × Δv) / Δt

Energy

• Kinetic Energy: KE = ½ × m × v²
• Gravitational Potential Energy: GPE = m × g × h
• Work Done: E = F × d (Work = Force × distance)
• Power: P = E / t (Power = Energy ÷ Time)
• Efficiency: efficiency = (useful energy out) ÷ (total energy in)
• Elastic Potential Energy: E = ½ × k × x²

Electricity and Magnetism

• Charge Flow: Q = I × t (Q = charge in Coulombs, I = current in Amps, t = time in seconds)
• Voltage / Potential Difference: V = I × R
• Electrical Power: P = I × V or P = I² × R
• Energy Transferred: E = Q × V
• Energy in Circuits: E = I × V × t
• Force on Wire in Magnetic Field: F = B × I × l (B = magnetic field strength, I = current, l = length of wire)
• Transformer Ratio: Vp / Vs = Np / Ns (p = primary, s = secondary)
• Power in Transformers: Vp × Ip = Vs × Is (100% efficient only)

Waves, Density, and Pressure

• Wave Speed: v = f × λ (v = speed, f = frequency, λ = wavelength)
• Density: ρ = m / V (mass ÷ volume)
• Pressure: P = F / A (Force ÷ Area)
• Liquid Pressure: P = h × ρ × g (h = depth, ρ = density, g = gravity)
• Gas Pressure: P₁ × V₁ = P₂ × V₂ (constant temperature)

Springs and Moments

• Force on a Spring: F = k × x (k = spring constant, x = extension)
• Moment (Turning Force): M = F × d (Force × distance from pivot)

Thermal Physics

• Thermal Energy (Heating): ΔQ = m × c × Δθ (c = specific heat capacity, Δθ = temperature change)
• Latent Heat: Q = m × L (L = specific latent heat)