Resonance Calculators
Resonance is a sympathetic phenomenon in which two objects experience the same common frequency (either directly or via harmonics). It also describes when a dynamic system reaches a state of minimal energy loss and/or minimal energy input needed to continue its state. Our calculators below will assist you in your resonance calculations in both acoustic and electrical systems.
Acoustic Resonance in Various Media
In order to calculate resonant frequencies in a sonic sense, we need to know two of three of the following values: the wavelength, the speed of the wave through the known medium, and the frequency of the oscillations. The velocity of a sound wave through a string can be calculated by knowing the tension of the string as well as the mass per unit length. Use the given calculator to find the velocity (v in m/s) of sound through your medium, or enter it below. Then enter the wavelength (λ in meters) of the system to find the resonant frequency (f in Hz). Alternatively, you can enter the resonant frequency to find the associated wavelength that would produce that frequency with the corresponding given wave velocity.
Note: You must have a value entered in the velocity box to calculate either the wavelength or resonant frequency.
Once you have the resonant frequency of a system, you can multiply that value by any whole number "N" to give the Nth harmonic of the system.
Note: You must have a value entered in the velocity box to calculate either the wavelength or resonant frequency.
Once you have the resonant frequency of a system, you can multiply that value by any whole number "N" to give the Nth harmonic of the system.
To calculate the velocity of a sound wave through a medium, enter the tension or stiffness (in Newtons) and density as mass per unit length (in kg/m), then click "Calculate Velocity".
Enter the velocity of sound through the medium by clicking "Air" or "Water", or by entering your own value.
Enter the wavelength of the system, or the frequency, and click on the corresponding button to find the unknown value.
Resonance in Electrical Circuits
Resonance in an LC circuit, or tank/resonant circuit, occurs when the reactance of the capacitor and the reactance of the inductor are equal. Since the inductive reactance increases as frequency increases, and the capacitive reactance decreases as the frequency increases, there is a "sweet spot" frequency where these two reactances are equal. This frequency is the resonant frequency of the circuit. Note that when the inductive and capacitive reactances are equal, the total impedance of the system goes to infinity and thus the circuit pulls no current from the power source when the circuit is in resonance.
To find the resonant frequency (F in Hz) of a resonant circuit, enter the capacitance (C in Farads) and the inductance (L in Henrys) and click "Calculate Resonant Frequency". Alternatively, enter the values for two knowns and click the appropriate button to calculate the unknown.