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:
because they are plastic shopping bags are increasingly recyclable or biodegradable .Traditional plastic bags are usually made from polyethylene, which consists of long chains of ethylene monomers. Ethylene is derived from natural gas and petroleum. The polyethylene used in most plastic shopping bags is either low-density (resin identification code or, more often, high-density (resin identification code.Color concentrates and other additives are often used to add tint to the plastic. Plastic shopping bags are commonly manufactured by blown film extrusion.
Explanation:
Answer:
Active genotype - environmental effects
Explanation:
There are primarily three types of co-relation between genotype and environment which are as follows –
a) Passive genotype –environment effect – This depicts the relationship between the genetic characteristics acquired by a child from his/her parents and the environment in which he/she is raised.
b) Reactive genotype –environment effect – This represents a relationship between genetically acquired behaviour from parents and the reaction corresponding to such behaviour.
c) Active genotype –environment effect – This represents a relationship between genetic tendency of an individual and the environment condition selected by an individual .
Answer:
It would be heat and pressure
Explanation:
If sedimentary rock becomes buried deep enough within the crust to be subjected to increased temperature and pressure, it may change into metamorphic rock.
Answer:
19%
Explanation:
Weinberg equilibrium assumption is that the allele frequency remains the same from generation to generation.
thus, since the percentage of homozygous is 81 and that of heterozygous is 19%. going by the Weinberg assumption, it will remain the same in the next generation.