An electronic frequency counter, spectrum analyzer, or an oscilloscope, among others.
A much older method is by the use of vibrating reeds!
Meters were constructed using thin metal reeds, which were resonant at particular frequencies. For example, a meter used to measure 60 Hz. could have five reeds mounted in a horizontal plane. The reeds would be calibrated to vibrate at 58, 59, 60, 61, 62 Hz. When you would look at the face of a meter connected to house current (in the U.S., for instance) you could tell whether the frequency was high, low, or right on, by seeing which reed looked the "thickest", since they would vibrate vertically. They were so accurate, that you could even tell if the frequency was 59 1/2 Hz., for example!
Set your oscilloscope for the voltage and read in cycles per second applying a prefix if needed. Hertz, kilohertz, Megahertz, Gigahertz. Well I doubt it can handle the last two.
Hertz (cycles/second) measures frequency or pitch. Decibels measures loudness or sound pressure.
Hertz measures the pitch, the tone of a sound, not how loud it is.
Hertz
This instrument is a balance.
A tiltmeter measures changes in the tilt of the earth. :)A tiltmeter is an instrument that measures changes in the tilt of the earth. :)
That is possibly the input impedance of a loudspeaker - not an impedance of an amplifier.
Hz is hertz which measures sound.
A calorimeter measures heat. In contrast, a thermometer measures temperature.A thermometer bolometer - an instrument that measures heat radiation; extremely sensitive calorimeter - a measuring instrument that determines quantities of heatHeat is measured with a ThermometerThermometerThermometer or calorimeterThermometerthermometerHeat is measured with a thermometer.
The clock speed is measures in Mega Hertz (MHz)
A thermometer measures molecular energy.
a calender
ruler