**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^{-9}m = 3 ×10^{-7}m

Also, we know that speed of light = 3×10^{8}m

therefore, the frequency is 1 × 10^{15}Hz.

**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.