Wavelength-Frequency Calculator
Convert between wavelength, frequency, and wave speed for electromagnetic and mechanical waves
Wave Principle: All waves obey the fundamental equation: speed = wavelength × frequency. For light in a vacuum, speed is constant (~3×10⁸ m/s).
Wave Type
Wave Properties
Wavelength:
0.00 m
Frequency:
0.00 Hz
Wave Speed:
0.00 m/s
Period:
0.00 s
Wavenumber:
0.00 rad/m
Angular Frequency:
0.00 rad/s
Wave Characteristics:
- Electromagnetic waves travel at light speed in vacuum
- Sound waves travel ~343 m/s in air at 20°C
Understanding Wave Relationships
Electromagnetic Spectrum
- Radio waves: >1mm to 100km wavelength
- Visible light: 380-750nm (violet to red)
- X-rays: 0.01-10nm wavelength
- Gamma rays: <0.01nm wavelength
Sound Waves
- Infrasound: <20Hz (below human hearing)
- Audible range: 20Hz-20kHz (human hearing)
- Ultrasound: >20kHz (medical imaging)
- Speed varies with medium: ~1480 m/s in water
"The visible spectrum represents just 0.0035% of the entire electromagnetic spectrum, yet it's the only portion our eyes can detect."
Wave Equations and Constants
Fundamental Wave Equation
Where:
v = wave speed (m/s)
λ = wavelength (m)
f = frequency (Hz)
Derived Wave Properties
Period (T):
Wavenumber (k):
Angular frequency (ω):
Photon energy (E):
h = Planck's constant (4.135667696×10⁻¹⁵ eV·s)
Standard Wave Speeds
Electromagnetic Waves
- Vacuum: 299,792,458 m/s (exact)
- Air: ~3×10⁸ m/s (0.03% slower)
- Water: ~2.25×10⁸ m/s (75% speed)
- Glass: ~2×10⁸ m/s (67% speed)
Sound Waves
- Air (20°C): 343 m/s
- Water: 1,480 m/s
- Steel: 5,960 m/s
- Rubber: 1,600 m/s
Note: The speed of sound varies with temperature in air: v ≈ 331 + (0.6 × T) m/s, where T is temperature in °C.
Frequently Asked Questions
Why does light slow down in materials but sound speeds up?
Light slows down in materials due to interactions with electrons in the medium. Sound speeds up in denser materials because the particles are closer together, allowing vibrations to transmit faster. These are fundamentally different wave types - electromagnetic vs. mechanical.
How do you convert between wavelength and photon energy?
For electromagnetic waves, use E = hc/λ where h is Planck's constant (6.626×10⁻³⁴ J·s) and c is light speed. Our calculator automatically computes photon energy in electron volts (eV) for convenience in physics applications.
What's the relationship between color and wavelength?
Visible light wavelengths correspond to colors: violet (~380-450nm), blue (~450-495nm), green (~495-570nm), yellow (~570-590nm), orange (~590-620nm), and red (~620-750nm). The calculator shows color approximations when wavelengths fall in the visible spectrum.
Why can't sound travel through a vacuum?
Sound requires a medium (air, water, solid) to propagate as it's a mechanical wave involving particle vibrations. In a vacuum, there are no particles to vibrate and transmit the wave energy. Light, being electromagnetic, doesn't require a medium.
How does frequency affect wave energy?
For electromagnetic waves, energy is directly proportional to frequency (E = hf). Higher frequency waves (like gamma rays) carry more energy per photon than lower frequency waves (like radio waves). For sound, frequency determines pitch but not necessarily energy.