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Energy of Waves: Amplitude, Frequency & Energy Loss. Wave Period: Definition & Formula. Vibrations . equation for frequency and period. This rate of 2 cycles/second is referred to as the frequency of the wave. As an example of the distinction and the relatedness of frequency and period, consider a woodpecker that drums upon a In equation form, this is expressed as follows. The wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a.
Frequency refers to how often something happens. Period refers to the time it takes something to happen. Frequency is a rate quantity. Period is a time quantity. As an example of the distinction and the relatedness of frequency and period, consider a woodpecker that drums upon a tree at a periodic rate. If the woodpecker drums upon a tree 2 times in one second, then the frequency is 2 Hz.
Each drum must endure for one-half a second, so the period is 0.
Frequency and Period of a Wave
If the woodpecker drums upon a tree 4 times in one second, then the frequency is 4 Hz; each drum must endure for one-fourth a second, so the period is 0. If the woodpecker drums upon a tree 5 times in one second, then the frequency is 5 Hz; each drum must endure for one-fifth a second, so the period is 0. Do you observe the relationship?
Mathematically, the period is the reciprocal of the frequency and vice versa. In equation form, this is expressed as follows. Since the symbol f is used for frequency and the symbol T is used for period, these equations are also expressed as: The quantity frequency is also confused with the quantity speed. The speed of an object refers to how fast an object is moving and is usually expressed as the distance traveled per time of travel.
Lesson Frequency, Wavelength, & Amplitude
For a wave, the speed is the distance traveled by a given point on the wave such as a crest in a given period of time. So while wave frequency refers to the number of cycles occurring per second, wave speed refers to the meters traveled per second. A wave can vibrate back and forth very frequently, yet have a small speed; and a wave can vibrate back and forth with a low frequency, yet have a high speed.
Frequency and speed are distinctly different quantities. Wave speed will be discussed in more detail later in this lesson.
How do changes in the frequency of a wave affect the wavelength of a wave? Use the Wave plotter widget below to find out. Alter the frequency and observe how the pattern changes. It is named after Heinrich Hertzone member of the Hertz family that made many important contributions to physics.
In formulas frequency appears as an "f". Since frequency and period are exact inverses of each other, there is a very basic pair of formulas you can use to calculate one if you know the other… It is very easy to do these calculations on calculators using the x-1 button.
The period of a pendulum is 4. Determine the frequency of this pendulum.
The period means that it will take 4. So, I expect that my frequency will be a decimal, since it will complete a fraction of a swing per second.
Wavelength Wavelength is a property of a wave that most people once they know what to look for can spot quickly and easily, and use it as a way of telling waves apart.
Look at the following diagram Figure 1 Any of the parts of the wave that are pointing up like mountains are called crests. Any part that is sloping down like a valley is a trough. Wavelength is defined as the distance from a particular height on the wave to the next spot on the wave where it is at the same height and going in the same direction.
Usually it is measured in metres, just like any length. Most people do like to measure from one crest to the next crest or trough to troughjust because they are easy to spot. Figure 2 On a longitudinal wave, the wavelength is measured as the distance between the middles of two compressions, or the middles of two expansions. Figure 3 This leads us to one of the most important formulas you will use when studying waves.
Frequency tells us how many waves are passing a point per second, the inverse of time. Wavelength tells us the length of those waves in metres, almost like a displacement. A wave is measured to have a frequency of 60Hz.