How to Calculate Frequency
What is Frequency?
A frequency calculator computes the frequency of a wave from its period, or vice versa. Also converts between frequency and wavelength using the wave speed equation.
Formula
Frequency = number of occurrences / total time period; Period (T) = 1 / frequency; Hz = cycles per second
- f
- Frequency (Hz (cycles/sec))
- T
- Period (seconds)
- n
- Number of cycles (count)
Step-by-Step Guide
- 1f = 1/T (frequency = 1 / period)
- 2T = 1/f (period = 1 / frequency)
- 3For electromagnetic waves: λ = c/f where c = speed of light
- 4For sound: λ = v_sound/f where v_sound ≈ 343 m/s at 20°C
Worked Examples
Input
Period T = 0.005 seconds
Result
f = 1/0.005 = 200 Hz
Input
Radio frequency 100 MHz
Result
λ = 3×10⁸/10⁸ = 3 metres
Frequently Asked Questions
What's a hertz?
1 Hz = 1 cycle per second. AC power is 50 Hz (UK) or 60 Hz (USA).
How do frequency and wavelength relate?
Wavelength (λ) = speed (c) / frequency (f). Higher frequency = shorter wavelength.
Can I measure frequency at home?
Yes, using oscilloscopes, frequency meters, or smartphone apps for sound. Requires appropriate equipment for precise measurement.
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