Wavelength....................................:)
<span>What is the quality of the sound of a fire truck’s siren when it moves toward a stationary hearer?
Its High Pitched
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What is the quality of the sound of a fire truck’s siren when it moves away from a stationary hearer?
Its Low Pitched
The correct answer is I disagree. Elements form all pure substances, but some pure substances include elements bonded together to form molecules and compounds.
Elements are pure substances but these elements also make other things such as water. The water molecule is made of two elements called oxygen and Hydrogen. Now water itself is a pure substance as it is chemically bonded hydrogen and Oxygen but it is composed of more than one element
The answer - all of the above.
X -rays are applied in many ways and for various purposes in every day life. They are defined as powerful waves of electromagnetic energy. They are able to penetrate most materials both organic and inorganic.
Their ability to penetrate organic material has made them especially useful in medicine where they can penetrate the body and reveal internal structures such as bones and organs.
In the airports, they are used for security purposes to check in luggage bags for prohibited or dangerous items.
In art, they are widely used by authenticators check for types of paper, materials, changes of composition and other clues to help establish authenticity of art pieces.
