# Demonstrate the relationship among frequency amplitude wavelength and wave velocity

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This lesson will guide you through the five wave parameters - Energy of Waves: Amplitude, Frequency & Energy Loss. Wave Period: . This equation represents the relationship between frequency and period. In science, we use a lowercase v to symbolize speed because it's also called velocity. None. For any wave, the amplitude can be anything. There is a simple relationship between wavelength, frequency, and velocity. You can see this easily: a wave. Like all other waves (waves in a string, water waves, sound, earthquake waves. A basic relation between wavelength, frequency and velocity results from the.

Putting a lot of energy into a transverse pulse will not effect the wavelength, the frequency or the speed of the pulse. The energy imparted to a pulse will only affect the amplitude of that pulse.

Consider two identical slinkies into which a pulse is introduced. If the same amount of energy is introduced into each slinky, then each pulse will have the same amplitude. But what if the slinkies are different?

What if one is made of zinc and the other is made of copper? Will the amplitudes now be the same or different? If a pulse is introduced into two different slinkies by imparting the same amount of energy, then the amplitudes of the pulses will not necessarily be the same. In a situation such as this, the actual amplitude assumed by the pulse is dependent upon two types of factors: Two different materials have different mass densities.

The imparting of energy to the first coil of a slinky is done by the application of a force to this coil. More massive slinkies have a greater inertia and thus tend to resist the force; this increased resistance by the greater mass tends to cause a reduction in the amplitude of the pulse. Different materials also have differing degrees of springiness or elasticity.

A more elastic medium will tend to offer less resistance to the force and allow a greater amplitude pulse to travel through it; being less rigid and therefore more elasticthe same force causes a greater amplitude. Energy-Amplitude Mathematical Relationship The energy transported by a wave is directly proportional to the square of the amplitude of the wave. This energy-amplitude relationship is sometimes expressed in the following manner. This means that a doubling of the amplitude of a wave is indicative of a quadrupling of the energy transported by the wave.

A tripling of the amplitude of a wave is indicative of a nine-fold increase in the amount of energy transported by the wave. And a quadrupling of the amplitude of a wave is indicative of a fold increase in the amount of energy transported by the wave.

The table at the right further expresses this energy-amplitude relationship. Observe that whenever the amplitude increased by a given factor, the energy value is increased by the same factor squared.

For example, changing the amplitude from 1 unit to 2 units represents a 2-fold increase in the amplitude and is accompanied by a 4-fold 22 increase in the energy; thus 2 units of energy becomes 4 times bigger - 8 units.

As another example, changing the amplitude from 1 unit to 4 units represents a 4-fold increase in the amplitude and is accompanied by a fold 42 increase in the energy; thus 2 units of energy becomes 16 times bigger - 32 units. Earthquakes and other geologic disturbances sometimes result in the formation of seismic waves.

Seismic waves are waves of energy that are transported through the earth and over its surface. This lesson will guide you through the five wave parameters - period, frequency, amplitude, wavelength, and speed - that we use to characterize waves.

Wave Parameters So, we've learned a little bit about waves, right? We've learned that waves originate from vibrations, which are oscillating motions over a fixed position. A vibration can cause a disturbance to travel through a medium, transporting energy without transporting matter. This is what a wave is. But, how do we properly talk about waves? How do we compare them to one another? Can we measure the size and speed of a wave?

How do we know how much energy it carries?

## Energy Transport and the Amplitude of a Wave

To find out, we'll need to look at the major wave parameters: We'll learn how to characterize a wave by its period, frequency, amplitude, speed, and wavelength. Once we get to know the right way to use these parameters, we'll be able to learn more about how the different waves work. These are the parts of the wave that are used to measure speed and size.

Let's start off by remembering what a wave looks like.

**Sound: Wavelength, Frequency and Amplitude.**

We've seen the picture above before. It's a wave drawn over a set of X and Y axes. We plotted the wave as a function of time and said that the portion of a wave between two crests or troughs is called a wave cycle. From this image, we can see that waves travel by crests and troughs in a periodic fashion. That is, a full wave cycle always takes the same amount of time. In this case, that amount of time is exactly two seconds.

- Wave Parameters: Wavelength, Amplitude, Period, Frequency & Speed
- The Wave Equation

Two seconds is called the period of the wave. Period and Frequency The period is the time it takes a wave to complete one cycle.

We measure the period in seconds, and we symbolize it with the capital letter T. You can think of the period as the time it takes for one particle in the medium to move back and forth.

### Velocity, Amplitude, Wavelength, And Frequency - The Measures Of A Wave

If this were a water wave, all the particles in the water would be moving up and down as the wave travels through. The time it takes for one water molecule to move up, move back down, and then return to its original position, is called the period.

Knowing the period of a wave is fine, but we often need to talk about waves in terms of how often the wave cycles are coming. In other words, we want to know the frequency of a wave.