Answer and Explanation: 1 — The medium for seismic waves is the Earth. A medium is any substance that a wave travels through. Since seismic waves travel through Earth, this is their medium. There are two main types of seismic waves, surface and body waves.
What does a seismic wave travel through?
Types of Seismic Waves — There are several different kinds of seismic waves, and they all move in different ways. The two main types of waves are body waves and surface waves. Body waves can travel through the Earth’s inner layers, but surface waves can only move along the surface of the planet like ripples on water. The body waves (P and S) and surface waves recorded by a seismometer. Body Waves.
Do seismic waves need a medium?
Common types of mechanical waves include sound or acoustic waves, ocean waves, and earthquake or seismic waves. In order for compressional waves to propagate, there must be a medium , i. matter must exist in the intervening space.
Which seismic wave can travel through all mediums?
P versus S waves — Seismologists are scientists who study earthquakes. They also study how a quake’s energy spreads through Earth’s crust, as well as the deeper layers of our planet. The fastest seismic waves are known as P waves. That «p» stands for primary. This gif depicts the movement of a type of seismic vibration known as a P wave. Lawrence Braile/Purdue University At Earth’s surface, P waves travel somewhere between 5 and 8 kilometers per second (3. 1 and 5 miles per second). Deeper within the planet, where pressures are higher and material is typically more dense, these waves can travel up to 13 kilometers per second (8.
And early seismologists called them that because these waves were the first to arrive at seismometers from some distant quake. 1 miles per second). P waves travel through rock the same way that sound waves do through air.
That is, they move as pressure waves. When a pressure wave passes a certain point, the material it is passing through moves forward, then back, along the same path that the wave is traveling. P waves can travel through solids, liquids and gases. That’s one big difference between them and the other types of seismic waves, which typically travel only through solids (such as rock). This gif depicts the movement of a type of seismic vibration known as an S wave. Lawrence Braile/Purdue University In general, S waves are only 60 percent as fast as p waves. So, along Earth’s surface they move at speeds of between 3 and 4. 8 kilometers per second (1. 9 and 3 miles per second). As an S wave passes through a material, the site of its passing moves from side to side or up and down (as compared to the direction the wave is traveling).
The next-fastest type of seismic waves are «secondary. » They earned that name because they were typically the second set to reach seismometers from a distant quake. Not surprisingly, they’re known as S waves.
This is why S waves are also known as transverse waves. «Transverse» comes from the Latin words for «turned across. «) S waves cannot travel through liquids or gases. That’s because the types of stresses set up by those waves can only be transmitted through solid materials.
How do seismic waves travel through Earth?
Related Animations — Seismic shadow zones have taught us much about the inside of the earth. This shows how P waves travel through solids and liquids, but S waves are stopped by the liquid outer core. Animation Novice The wave properties of light are used as an analogy to help us understand seismic-wave behavior. Animation Novice The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The different phases show how the initial P wave changes when encountering boundaries in the Earth. Animation Novice The shadow zone results from S waves being stopped entirely by the liquid core. Three different S-wave phases show how the initial S wave is stopped (damped), or how it changes when encountering boundaries in the Earth. Animation Novice Seismic waves travel a curving path through the earth due to changes in composition, pressure, and temperature within the layers of the Earth. Animation Novice Seismic waves travel at different speeds through different materials. In this 2-layer model two wave fronts leave an impact at the same time but the lower layer is faster. Animation Novice Seismic waves travel a curving path through the earth due to changes in composition, pressure, and temperature within the layers of the Earth. Animation Novice Animation shows the race between the direct seismic wave vs. the deeper, longer-path critically refracted seismic wave. Graph records the arrival times. Animation Novice In this model of increasing velocity with depth, the critically refracted seismic rays speed up with depth as they pass 5 different velocity boundaries. Animation Intermediate In this model of increasing velocity with depth, the critically refracted seismic rays speed up with depth as they pass 5 different velocity boundaries. Animation Intermediate Animation Intermediate.
What medium do seismic waves travel through Brainpop?
Text reads: The Mysteries of Life with Tim and Moby A robot, Moby, is playing with a Slinky toy on a staircase. The toy moves down the steps, away from Moby. Moby weeps. MOBY: Beep. Beep. Beep. A boy, Tim, reads from a typed letter. TIM: Dear Tim and Moby, Are light waves, sound waves, and ocean waves all the same thing? From, Danny.
- Well, all waves do the same basic thing: transfer energy from one place to another;
- But physicists divide waves into two basic kinds: mechanical and electromagnetic;
- Images show a mechanical wave and an electromagnetic wave;
TIM: Ocean waves, seismic waves, sound waves, and Slinky waves are all mechanical waves, because they need a medium to move through. Images show the four kinds of mechanical waves as Tim names them. MOBY: Beep. TIM: Well, a medium is any kind of matter that’s disturbed by energy.
That energy disperses through the medium in the form of waves, which are basically chains of vibrating molecules. An animation shows a rock dropping into a pond. TIM: Water waves move energy through the medium of water molecules.
Animations show ripples and moving water molecules. TIM: Sound waves can transfer energy through a medium of air, liquid, or solid molecules. An animation shows a tuning fork being struck and waves going into the air. TIM: Seismic waves travel through the ground, usually after an earthquake.
An animation shows a neighborhood shaking. TIM: And Slinky waves move through the medium of individual loops. An animation shows a Slinky going down a staircase. TIM: Slinkies are really useful for visualizing how mechanical waves work.
You can think of each ring as an individual molecule. An image shows slinky rings split into individual molecules in a horizontal row. TIM: When you shake one end of the toy, you can see how the kinetic energy moves from one Slinky molecule to the next. Mechanical waves may appear to move matter forward with them, but that’s not the case.
Just like with a Slinky’s rings, a molecule disturbed by a wave will return to its original resting position after it’s passed the energy on to its neighbors. The slinky molecules move in a wave formation to illustrate Tim’s explanation.
MOBY: Beep. TIM: Electromagnetic waves, like light and radio waves, don’t need a medium to move through; they can travel through completely empty space. An image shows the spectrum of electromagnetic waves, from gamma waves to radio waves, including the range of visible light.
TIM: That’s why light waves from the Sun and stars are able to reach Earth. An animation shows the Sun’s rays shining on the earth. TIM: And why radio waves let us communicate with spacecraft. An image shows a NASA control room.
MOBY: Beep. TIM: Well, mechanical and electromagnetic waves are different, but they can be measured in many of the same ways. This particular wave is called a transverse wave. It carries energy along the spring by making it move at right angles to the direction of the energy flow.
- Tim holds one end of a long spring and moves it up and down, creating waves;
- TIM: Ocean waves and most electromagnetic waves move in a transverse pattern;
- The crest is the highest point of a transverse wave, and the trough is the lowest point;
That distance between the midpoint of the wave and the crest is the amplitude. That’s also a measure of how much energy the wave is carrying. More energy means a greater amplitude. The distance a wave travels in one wave cycle is one wavelength. That’s measured by finding the distance between two crests or two troughs.
An image shows a transverse wave with its parts labeled. MOBY: Beep. TIM: Waves can be measured by their frequency, too. The frequency is the number of waves that pass a given point in one second. It’s measured in hertz, or waves per second.
An animation illustrates waves of different frequencies passing a specific point. TIM: And frequency is related to wavelength. A wave with a short wavelength will have a high frequency, while a wave with a long wavelength will have a low frequency. Images show different wavelengths.
MOBY: Beep. Moby holds a boom box to his ear. He turns it on. There is static and random noise. TIM: Right. Sound travels in compressional waves. Unlike transverse waves, compressional waves displace matter back and forth in the same direction as the energy of the wave.
Tim and Moby each hold one end of a long spring. Tim gives his end a push and a compressional wave moves forward through the spring, toward Moby. TIM: Vibrations created by anything from your vocal cords, to a drum head, to breaking glass will push air molecules together, forming a series of compressions that travel through the air.
An animation shows compressional waves making contact with a human ear. TIM: Those compressing molecules hit your eardrum, making it vibrate and sending sound signals to your brain. Tim holds one end of a long spring.
TIM: Like I said, mechanical waves need something to travel through. Moby drifts through space wearing a spacesuit. TIM: That’s why you won’t hear sounds if you find yourself in outer space. Unless, of course, if you bring your own air. MOBY: Beep. TIM: Well, that’s about enough on waves for now.
What type of material would a seismic wave travel through fastest?
There are two types of body waves: P-waves travel fastest and through solids, liquids, and gases; S-waves only travel through solids. Surface waves are the slowest, but they do the most damage in an earthquake.
What travels through liquid medium?
Seismic Waves — When an earthquake occurs, it makes seismic waves, which cause the shaking we feel. Seismic waves are essentially just the jiggling of the ground in response to the force put on the ground by the earthquake, similar to the way the jello in a bowl responds to a tap to the side of the bowl.
There are three major kinds of seismic waves: P, S, and surface waves. P and S waves together are sometimes called body waves because they can travel through the body of the earth, and are not trapped near the surface.
A P wave is a sound wave traveling through rock. In a P wave, the rock particles are alternately squished together and pulled apart (called compressions and dilatations ), so P waves are also called compressional waves. These waves can travel through solids, liquids, and gases. An S wave is a different beast. In an S wave, the rock particles slide past one another, undergoing shear — so an S wave is also called a shear wave. You can make shear waves by, for example, tying a rope to a tree and shaking the free end of the rope up and down or side-to-side. The waves themselves will travel forward, toward the tree. Surface waves are called surface waves because they are trapped near the Earth’s surface, rather than traveling through the «body» of the earth like P and S waves. There are two major kinds of surface waves: Love waves, which are shear waves trapped near the surface, and Rayleigh waves, which have rock particle motions that are very similar to the motions of water particles in ocean waves. The images on this page come from the UPSeis program at Michigan Technological University.
Which waves can only travel through solid medium?
Answer. P waves can travel through solids, liquids and gases. That’s one big difference between them and the other types of seismic waves, which typically travel only through solids (such as rock).
What material do primary waves can pass through?
The shifting rock in an earthquake causes vibrations called seismic waves that travel within Earth or along its surface. Scientists use an instrument called a seismograph to record data about seismic waves. This information yields information that can help scientists learn not only about earthquake behavior but also about the structure of Earth itself.
- There are two broad classes of seismic waves: body waves and surface waves;
- Body waves travel within the body of Earth;
- They include P, or primary, waves and S, or secondary, waves;
- P waves cause the ground to compress and expand, that is, to move back and forth, in the direction of travel;
They are called primary waves because they are the first type of wave to arrive at seismic recording stations. P waves can travel through solids, liquids, and even gases. S waves shake the ground in a shearing, or crosswise, motion that is perpendicular to the direction of travel.
These are the shake waves that move the ground up and down or from side to side. S waves are called secondary waves because they always arrive after P waves at seismic recording stations. Unlike P waves, S waves can travel only through solid materials.
After both P and S waves have moved through the body of Earth, they are followed by surface waves, which travel along Earth’s surface. Surface waves travel only through solid media. They are slower-moving than body waves but are much larger and therefore more destructive.
The two types of surface waves are named Love waves and Rayleigh waves, after the scientists who identified them. Love waves have a horizontal motion that moves the surface from side to side perpendicular to the direction the wave is traveling.
Of the two surface waves, Love waves move faster. Rayleigh waves cause the ground to shake in an elliptical pattern. This motion is similar to that observed in ocean waves. Of all the seismic waves, Rayleigh waves spread out the most, giving them a long duration on seismograph recordings..
Which seismic waves can travel through all the three states?
During an earthquake, accumulated tension is released in massive waves to cause the trembling at the surface of the earth. These waves are called seismic waves and are of three types – 1) Primary Seismic Waves or P waves — • The waves that reach the earth’s surface first once energy is emitted from the earth’s surface are called primary seismic waves.
• These waves can travel through all the three mediums of liquid, solid and gaseous states. • They have high velocity and move in a radial direction from the focus of the earthquake. • These waves are often called forward-backward waves as particles through which these waves pass tend to move to and fro in the direction of the waves.
• Initial waves are felt but are not damaging to a great extent. 2) Secondary Seismic Waves or S waves — • The waves that reach the earth’s surface after the primary waves once energy is emitted from the earth’s surface are called secondary seismic waves.
• These waves can travel through only solid state medium and get absorbed in any liquid state mediums. • They have lower velocity than Primary waves and scatter in all directions from the earthquake focus point.
• These waves cause the particles it passes through to move up and down. • These waves are more damaging causing the maximum destruction during an earthquake. 3) Surface Seismic Waves or L waves – • These waves are generated after the main P and S waves reach the epicenter.
What does P and S-waves stand for?
Categories: Seismic Waves | Local P and S September 10, 2008 The magnitude 4. 0 earthquake, which struck under Alamo last Friday night, was felt widely in the greater Bay Area, from Half Moon Bay in the west all the way to Stockton in the east. Many people noticed two distinct jolts, just a few seconds apart. In Orinda, where we were still sitting at the dinner table with family and guests, the two shocks were almost equally strong with about three seconds between them. Such two separate rumbles are not a sign of two individual earthquakes. Instead they are a consequence of two kinds of seismic waves, which are radiated from every earthquake focus. One type is called a compressional wave, because the seismic energy compresses and releases the ground periodically as the wave passes through.
- During the shaking, the ground moves in the direction of the propagating wave;
- (see Fig;
- The other type is called a shear wave, because it make the ground move perpendicular to the wave direction (see Fig;
2) Compressional waves are also called P-Waves, (P stands for «primary») because they are always the first to arrive. They gave us the first jolt last Friday. Shear waves propagate more slowly through the Earth than compressional waves and arrive second, hence their name S- or secondary waves. Looking at a seismogram of the Alamo earthquake (Fig. 3) the time difference between the arrivals of P- and S- waves is 3. 5 seconds. This seismogram was recorded at our station BKS, which is located in Strawberry Canyon in the Berkeley Hills above campus. Applying the rule of thumb, we get a distance to the earthquake focus of approximately 17.
- They were responsible for the second rumble;
- The difference in arrival time between these two types of seismic waves can be used as a rough estimate of the distance to the earthquake focus;
- As a rule of thumb: Multiply the time between the two jolts by 5 and you get the distance to the focus in miles;
5 miles. The result is pretty good, as the actual distance is exactly 16. 5 miles. (hra002).
Which type of seismic waves can travel through liquids?
SF Table 7. 1 shows that P waves have a higher velocity than S waves when traveling through several mineral types. The speed at which seismic waves travel depends on the properties of the material that they are passing through. For example, the denser a material is, the faster a seismic wave travels (SF Table 7.
|Mineral||P wave velocity (m/s)||S wave velocity (m/s)||Density (g/cm 3 )|
|Soil||300-700||100-300||1. 7-2. 4|
|Dry sand||400-1200||100-500||1. 5-1. 7|
|Limestone||3500-6000||2000-3300||2. 4-2. 7|
|Granite||4500-6000||2500-3300||2. 5-2. 7|
|Basalt||5000-6000||2800-3400||2. 7-3. 1|
SF Fig. 4 shows wave propagation through Earth. Note that P waves pass through all layers of the earth, while S waves cannot pass through the solid core of the earth, resulting in an S wave shadow on the opposite side of the earthquake.