By measuring the distance between the wave peaks!! It depends which country or region you are talking about. If you have two waves, or two things in oscillation or two things in vibration; if the peaks maximum amplitude and valleys maximum amplitude the other way occur at the same time then they are in phase.
If one wave peaks at the same time the other one is in a valley they are said to be degrees out of phase. The first little bump is the P wave it is followed by the QRS Complex that's the big spike and that is followed by the T wave which is a bigger bump than the P wave A periodic wave done using a rope is for example a sine wave.
Log in. Electronics Engineering. Electrical Engineering. Study now. See Answer. Best Answer. All of them. Electromagnetic, sound, even a water wave until it hits shore. Study guides. Physics 20 cards. A wave has a frequency of hertz what is the period of the wave. In which material does sound travel the fastest. In this type of wave particles of the medium vibrate perpendicularly to the direction of the wave itself. A 5 ohm resistor a 10 ohm resistor and a 15 ohm resistor are connected in series to a volt power source What is the amount of current flowing between the 5 ohm resistor and the 10 ohm resistor.
Electrical Engineering 21 cards. Could you give me an example of a simple sentence. In what kind of circuit is the voltage the same across all branches. How is the wiring done in houses and other occupied buildings.
In a series circuit the is the same at every point. To visualize the idea of the speed of the wave, imagine that the figure is showing a snapshot of the wave at one instant of time, and that the whole repeating waveform is moving from left to right. From the perspective of a fixed point on the x axis the horizontal line , we would see a succession of peaks and valleys passing by. The frequency of the wave would be given by the number of peaks or valleys that we see passing us per unit of time.
The wavelength is defined as the distance between equivalent points on the repeating waveform - such as the distance between two successive peaks.
The figure shows waveforms of two different wavelengths - the lower wave has a shorter wavelength than the top wave. If both waves are traveling at the same speed, then in observing the bottom wave from a fixed point, we would see more peaks passing us per unit time than if we were watching the top wave. Thus, the bottom wave would have a higher frequency than the top wave.
In fact, an important relationship that holds for all waves is the following:. One of our principal objectives is to use this relationship to convert between frequency and wavelength for any given value of either of these.
We may also find it necessary to use decimal multipliers for unit conversion, as frequencies and wavelengths of EM radiation vary over many orders of magnitude. As stated above, waves carry energy, but how much energy?
The energy a wave carries is related to its amplitude, which is one-half the distance between the wave's crest highest point and trough lowest point.
We can readily agree that a tsunami carries much more energy than a pond ripple. The amount of energy delivered by travelling waves such as ocean waves, sound waves, or the waves of EM radiation is time-dependent, so we can alternatively relate wave amplitude to power , or energy per unit time.
The power carried by a wave is proportional to the square of its amplitude and the square of its frequency. A related quantity, intensity I is defined as the power transmitted by the wave per unit area normal to the direction of propagation. Waves such as light or sound from a point source are three-dimensional, as opposed to the one-dimensional waveform shown above.
The intensity of a wave is also proportional to the square of the wave amplitude. Such repeating functions are termed periodic functions. We can introduce a phase factor into the waveform by adding a term to the argument of the sine function. It repeats itself in a periodic and regular fashion over both time and space. And the length of one such spatial repetition known as a wave cycle is the wavelength. The wavelength can be measured as the distance from crest to crest or from trough to trough.
In fact, the wavelength of a wave can be measured as the distance from a point on a wave to the corresponding point on the next cycle of the wave. In the diagram above, the wavelength is the horizontal distance from A to E, or the horizontal distance from B to F, or the horizontal distance from D to G, or the horizontal distance from E to H. Any one of these distance measurements would suffice in determining the wavelength of this wave. A longitudinal wave is a wave in which the particles of the medium are displaced in a direction parallel to the direction of energy transport.
A longitudinal wave can be created in a slinky if the slinky is stretched out horizontally and the end coil is vibrated back-and-forth in a horizontal direction. If a snapshot of such a longitudinal wave could be taken so as to freeze the shape of the slinky in time, then it would look like the following diagram. Because the coils of the slinky are vibrating longitudinally, there are regions where they become pressed together and other regions where they are spread apart.
A region where the coils are pressed together in a small amount of space is known as a compression. A compression is a point on a medium through which a longitudinal wave is traveling that has the maximum density.
A region where the coils are spread apart, thus maximizing the distance between coils, is known as a rarefaction. A rarefaction is a point on a medium through which a longitudinal wave is traveling that has the minimum density. While a transverse wave has an alternating pattern of crests and troughs, a longitudinal wave has an alternating pattern of compressions and rarefactions.
As discussed above, the wavelength of a wave is the length of one complete cycle of a wave. For a transverse wave, the wavelength is determined by measuring from crest to crest. A longitudinal wave does not have crest; so how can its wavelength be determined? The wavelength can always be determined by measuring the distance between any two corresponding points on adjacent waves.
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