# What does s represent in ECG?

## What does s represent in ECG?

the R wave reflects depolarization of the main mass of the ventricles –hence it is the largest wave. the S wave signifies the final depolarization of the ventricles, at the base of the heart.

## What happens in the S wave?

This is known as an S wave and represents depolarisation in the Purkinje fibres. The S wave travels in the opposite direction to the large R wave because, as can be seen on the earlier picture, the Purkinje fibres spread throughout the ventricles from top to bottom and then back up through the walls of the ventricles.

secondary waves

## How do S waves move?

An S wave is slower than a P wave and can only move through solid rock, not through any liquid medium. ... S waves move rock particles up and down, or side-to-side--perpendicular to the direction that the wave is traveling in (the direction of wave propagation).

1 to 8 km/sec

## Why are P waves faster than S?

P-waves travel 60% faster than S-waves on average because the interior of the Earth does not react the same way to both of them. P-waves are compression waves that apply a force in the direction of propagation. ... The energy is thus less easily transmitted through the medium, and S-waves are slower.

## What are 4 types of seismic waves?

There are three basic types of seismic waves – P-waves, S-waves and surface waves. P-waves and S-waves are sometimes collectively called body waves.

## What are P and S waves?

P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. ... The different S waves arrive after the P waves. The slowest (and latest to arrive on seismograms) are surface waves, such as the L wave.

## What happens to S and P waves as they travel inside Earth?

The speed of P waves and S waves increases as they travel deeper into the Earth's mantle . They travel through the Earth in curved paths, but they change direction suddenly when they pass through the boundary between substances in different states.

## What are the 2 types of body waves?

Body waves are of two types: Primary waves (also called P-waves, or pressure waves) and Secondary waves (S-waves, or shear waves). P-waves are compression waves. They can propagate in solid or liquid material. S-waves are shear waves.

## What are 2 main types of seismic waves?

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.

## What are the characteristics of S waves?

S-waves are shear waves (though that is not what the S stands for). They move by material flexing or deforming sideways (shearing) from the direction of wave travel, and then returning to the original shape once the wave passes.

transverse waves

## Why do S waves cause more damage than P waves?

S waves, or secondary waves, come next since they travel more slowly than P waves. ... S waves are more dangerous than P waves because they have greater amplitude and produce vertical and horizontal motion of the ground surface. The slowest waves, surface waves, arrive last. They travel only along the surface of the Earth.

## Where are S waves detected?

S-waves are not detected on the opposite side of the Earth - this suggests that the mantle has solid properties, but the outer core must be liquid. P-waves are detected on the opposite side of the Earth. Refractions between layers cause two shadow zones where no P-waves are detected.

## Which wave do you think can cause the most damage to structures?

Surface waves, in contrast to body waves can only move along the surface. They arrive after the main P and S waves and are confined to the outer layers of the Earth. They cause the most surface destruction. Earthquake surface waves are divided into two different categories: Love and Rayleigh.

## How are P and S waves detected?

The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core. Did You Know??? Through measuring how P and S waves travel through the earth and out the other side, a seismic wave shadow zone was discovered in about 1910.

## Are S waves longitudinal?

Body waves travel through the interior of the earth, and have two main types: P-Waves (Primary waves) are Longitudinal Waves. S-Waves (Secondary waves) are Transverse Waves.

## Are microwaves longitudinal or transverse?

Although both wave types are sinusoidal, transverse waves oscillate perpendicular to the direction of propagation, while longitudinal waves oscillate parallel to the direction of propagation. ... All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse. All sound waves are longitudinal.

## What is P waves or longitudinal waves?

The P seismic waves travel as elastic motions at the highest speeds. They are longitudinal waves that can be transmitted by both solid and liquid materials in the Earth's interior. With P waves, the particles of the medium vibrate in a manner similar to sound waves—the…

## Why S waves Cannot travel through liquid?

S-waves cannot travel through liquids. When they reach the surface they cause horizontal shaking. Liquids don't have any shear strength and so a shear wave cannot propagate through a liquid. Think of a solid material, like a rock.

## Can S wave travel through gas?

Shear waves cannot travel in liquids or gases -- so, for example, S waves don't travel through the ocean or through the outer core.

## In what material do S waves disappear?

S-waves disappear at the mantle core boundary, so the outer core is liquid. Other clues to Earth's interior includes the fact that we know that Earth's overall density is higher than the density of crustal rocks, so the core must be made of something dense, like metal.

## Which waves can travel through all the three states?

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.

solids

## Which waves travel faster through granite?

In air, they take the form of sound waves, hence they travel at the speed of sound. Typical speeds are 330 m/s in air, 1450 m/s in water and about 5000 m/s in granite. Secondary waves (S-waves) are shear waves that are transverse in nature.

## What does a normal P wave look like?

In a normal EKG, the P-wave precedes the QRS complex. It looks like a small bump upwards from the baseline. The amplitude is normally 0.

## What is the relationship between P and S waves?

P waves can travel through liquid and solids and gases, while S waves only travel through solids. Scientists use this information to help them determine the structure of Earth. For example, if an earthquake occurs on one side of Earth, seismometers around the globe can measure the resulting S and P waves.