<span>The movement of Alaskan and northern water currents southward down the west coast results in much cooler ocean temperatures than at comparable latitudes on the east coast of the United States, where waters currents come from the Caribbean and Tropical Atlantic.</span>
Explanation:
It is given that,
The wavelength of red helium–neon laser light in air is, ![\lambda=632.8\ nm=632.8\times 10^{-9}\ m](https://tex.z-dn.net/?f=%5Clambda%3D632.8%5C%20nm%3D632.8%5Ctimes%2010%5E%7B-9%7D%5C%20m)
(a) Frequency, ![f=\dfrac{c}{\lambda}](https://tex.z-dn.net/?f=f%3D%5Cdfrac%7Bc%7D%7B%5Clambda%7D)
![f=4.74\times 10^{14}\ Hz](https://tex.z-dn.net/?f=f%3D4.74%5Ctimes%2010%5E%7B14%7D%5C%20Hz)
(b) Let
shows its wavelength in glass that has an index of refraction of 1.51,
![\lambda_g=\dfrac{\lambda}{n}](https://tex.z-dn.net/?f=%5Clambda_g%3D%5Cdfrac%7B%5Clambda%7D%7Bn%7D)
![\lambda_g=\dfrac{632.8\times 10^{-9}\ m}{1.51}](https://tex.z-dn.net/?f=%5Clambda_g%3D%5Cdfrac%7B632.8%5Ctimes%2010%5E%7B-9%7D%5C%20m%7D%7B1.51%7D)
![\lambda_g=4.19\times 10^{-7}\ m](https://tex.z-dn.net/?f=%5Clambda_g%3D4.19%5Ctimes%2010%5E%7B-7%7D%5C%20m)
![\lambda_g=419\ nm](https://tex.z-dn.net/?f=%5Clambda_g%3D419%5C%20nm)
(c) Let
is its speed in the glass.
![v_g=\dfrac{c}{n}](https://tex.z-dn.net/?f=v_g%3D%5Cdfrac%7Bc%7D%7Bn%7D)
![v_g=\dfrac{3\times 10^8\ m/s}{1.51}](https://tex.z-dn.net/?f=v_g%3D%5Cdfrac%7B3%5Ctimes%2010%5E8%5C%20m%2Fs%7D%7B1.51%7D)
![v_g=1.99\times 10^8\ m/s](https://tex.z-dn.net/?f=v_g%3D1.99%5Ctimes%2010%5E8%5C%20m%2Fs)
Hence, this is the required solution.
Answer:
Physical Properties of Carbon:
Carbon is a unique element. It occurs in many forms. Some examples of the pure form of carbon are coal and soot.
It is soft and dull grey or black in colour.
One of the most important compounds of carbon is the charcoal, which is formed when carbon is heated in the absence in of air.
It occurs in a number of allotropic forms. Allotropes are nothing but forms of an element with varying physical as well as chemical properties.
The density of the different forms of carbon depends upon the origin of these elements. You will find some forms of carbon which are pure and some forms which are not pure like coal which is the mixture of both carbon and hydrogen.
Chemical Properties of Carbon
Carbon compounds generally show 4 reactions, they are
Combustion reaction
Oxidation reaction,
Addition reactions
Substitution reaction.
As we all know that carbon in all forms needs oxygen, heat, and light and forms carbon dioxide. When it is burned in air to give carbon dioxide, it is called as combustion.
Let us get the concept of this using some examples when it is burnt in the air: When methane CH4 is burnt in the presence of oxygen it gives us carbon dioxide, heat, and light.
Explanation:
Answer:
30 neutrons
Explanation:
A neutral iron atom contains 26 protons and 30 neutrons plus 26 electrons in four different shells around the nucleus. As with other transition metals, a variable number of electrons from iron's two outermost shells are available to combine with other elements.
The wave speed completely depends on the characteristics and properties of the medium . . . physical properties for mechanical waves, electrical properties for electromagnedtic waves.
So if you want to change the speed of a wave, you have to change the medium . . . shoot it through some different kind of stuff. <em>(B) </em>