Question-
Which seismic waves are felt first at a seismic station
Answer-
Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs.
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. Earthquakes radiate seismic energy as both body and surface waves.
BODY WAVES
Traveling through the interior of the earth, body waves arrive before the surface waves emitted by an earthquake. These waves are of a higher frequency than surface waves.
P WAVES
The first kind of body wave is the P wave or primary wave. This is the fastest kind of seismic wave, and, consequently, the first to 'arrive' at a seismic station. The P wave can move through solid rock and fluids, like water or the liquid layers of the earth. It pushes and pulls the rock it moves through just like sound waves push and pull the air. Have you ever heard a big clap of thunder and heard the windows rattle at the same time? The windows rattle because the sound waves were pushing and pulling on the window glass much like P waves push and pull on rock. Sometimes animals can hear the P waves of an earthquake. Dogs, for instance, commonly begin barking hysterically just before an earthquake 'hits' (or more specifically, before the surface waves arrive). Usually people can only feel the bump and rattle of these waves.
P waves are also known as compressional waves, because of the pushing and pulling they do. Subjected to a P wave, particles move in the same direction that the the wave is moving in, which is the direction that the energy is traveling in, and is sometimes called the 'direction of wave propagation'. Click here to see a P wave in action.
Answer:
Heterozygous dominant
Explanation:
because, as you know, heterozygous is different, and Dd has both dominant and recessive, making it heterozygous rather than homozygous.
Because the first d is dominant (capital D), then it makes the genotype dominant and heterozygous.
Mafic materials are usually dark in color and have relatively high specific gravities grater than 3.0 Felsic materials are usual at lighter in color and have specific gravities less than 3.0
The cell cycle or cell-division cycle is the series of events that take place in a cell leading to its division and duplication of its DNA (DNA replication) to produce two daughter cells.
Answer:
Twins occur.
Explanation:
If the embryo is divided into half by artificial methods such as microsurgical, twins occur in the female body. Both the embryo are identical to each other. twins means that there will be two babies formed at the same time in the body of female. After the separation of embryo, both the embryos are genetically identical to each other and it continue to develop into a new organisms.