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Physics Formula Reference

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97 references found. Results are rendered on the server and limited to 25 per page.

v = fλ

Wave Speed

waves optics · periodic waves

Relates propagation speed, frequency, and wavelength.

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y(x,t) = A sin(2π(x/λ − ft) + φ)

Periodic Wave

waves optics · periodic waves

Describes one sinusoidal travelling wave using amplitude, wavelength, frequency, and phase.

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f_beat = f_high − f_low

Beat Frequency

waves optics · sound

Gives beat frequency from two nearby source frequencies.

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I = P / A

Intensity

waves optics · sound

Relates average power crossing a surface to its area.

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L_I = 10 log₁₀(I / I₀)

Sound Intensity Level

waves optics · sound

Expresses sound intensity relative to a reference intensity on a logarithmic scale.

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nλ = d sin θ

Double-Slit Interference

waves optics · interference

States the constructive-interference condition for a two-slit pattern.

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n = c / v

Index of Refraction

waves optics · refraction

Relates a medium’s refractive index to light speed in that medium.

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n₁ sin θ₁ = n₂ sin θ₂

Snell's Law

waves optics · refraction

Relates incident and refracted angles across an interface.

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sin θ_c = n₂ / n₁

Critical Angle

waves optics · refraction

Gives the critical angle for light moving from higher to lower refractive index.

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1/f = 1/d₀ + 1/dᵢ

Thin Lens and Mirror Equation

waves optics · geometric optics

Relates focal length to object and image distances for an ideal thin lens or spherical mirror.

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M = hᵢ / h₀ = dᵢ / d₀

Linear Magnification

waves optics · geometric optics

Relates image-to-object size and distance ratios under the source convention.

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F = kq₁q₂ / r²