The right answer is B.
*Hydrogen is the most abundant element representing nearly three quarters of the mass of the universe.
*Hydrogen is found in the water that covers 70% of the surface of our planet as well as in all organic matter.
*Hydrogen is the simplest element in the universe. It is composed only of one proton (p) and only one electron (e-).
*Hydrogen is the lightest element of all elements and gases; it is 14 times lighter than air. A "spill" of hydrogen gas immediately diffuses into the air and pollutes neither the ground nor the water table.
*Hydrogen is invisible, odorless and nontoxic. It does not cause acid rain, does not deplete the ozone layer and does not generate dangerous emissions.
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.
Definition:
Having two different alleles of a particular gene or genes.
(an Allele is a variant form of a gene.)
Simplification:
If the organism has one copy of two different alleles, it is heterozygous.
Eg: T and t
<em> </em><em> </em><em> </em><em> </em><em> </em><em>(</em><em>T</em><em> </em><em>for </em><em>tall</em><em> </em><em>and</em><em> </em><em>t</em><em> </em><em>for</em><em> </em><em>short</em><em>)</em>
Example:
<u><em>Pea</em><em> </em><em>Plants</em></u>
Pea plants can have red flowers and either be homozygous dominant (red-red), or heterozygous (red-white). If they have white flowers, then they are homozygous recessive (white-white). Carriers are always heterozygous.
Answer:
Wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a vacuum at the same speed, the number of wave crests passing by a given point in one second depends on the wavelength.
Amplitude is the height of a wave which is the brightness of a light or loudness of a sound. So Frequency and Amplitude though are part of a wave are not dependent on each other. Their is no relation between frequency and amplitude.
Explanation:
hope it helps
