Frequency Formula
Small Description: Hertz is a unit of measurement for frequency (Hz). The frequency of such waves is calculated using the frequency formula.
The equation is used to determine a wave’s frequency. The number of iterations performed per unit time is known as frequency. It also shows how many crests pass past a specific spot in a given amount of time. It’s also known as the reciprocal of time. Hertz is a unit of measurement for frequency (Hz). The frequency of such waves is calculated using the frequency formula.
The total number of repetitions of a recurring event/unit of time is known as frequency. Depending on the quantities known, multiple frequency formulae can be used to compute frequency. The frequency of a wave is calculated using the formula for
- frequency (f)
- time period (T)
- wave speed (V)
- wavelength (λ)
One Hertz (Hz) is one cycle every second.
Various Formulae
where, T = time period. The above formula gives the relationship between frequency and time period. Both are inversely proportional to each other.
where, λ = wavelength of a wave and 𝜈 = wave speed. Here lambda (λ) is inversely proportional whereas wave number is directly proportional to the frequency.
where, ω = angular velocity.
Solved Examples
1. Calculate the frequency of a wave with a cycle time of 0.25 s using the frequency formula.
And T = 0.25 s given. Substituting in above equation we get,
f = 1/0.25 = 4
therefore, the frequency is 4 Hz
2. If the wavelength of the light is 300 nm, then find the frequency of that light wave.
Wavelength = 300 nm = 300 × 10-9m = 3 ×10-7m
Also, we know that speed of light = 3×108m
therefore, the frequency is 1 × 1015Hz.
3. Calculate the frequency of the pendulum that takes 12 seconds to complete one cycle.
Here, Time period (T) = 12 second.
f = 1/T = 1/12
f = 0.833
Therefore, the frequency of the pendulum is 0.833 Hz.
4. Determine the angular velocity of the wave, if the frequency is 20 hertz.
Here, f = 20 Hz.
Now using the formula for frequency, we get,
20 × 2π = ω
40π = ω
Therefore, the angular velocity is 40π.