perpendicular to the wave motion.
Answer
Hertzsprung-Russell (HR) diagram is an essential tool used in stellar evolution. In the universe, there are several hundreds of billions of stars. Scientists use the tool, in differentiation, the billions of stars in the world from the sun. In the HR tool, there is plotting of the luminosity or energy output of a star, which is plotted on the X-axis of a graph against the absolute magnitude. The sun's magnitude is an absolute of +48, which, when plotted against its luminosity, helps in setting an apparent variance between the sun and any other star. Additionally, the sun has been identified as the primary star with a very high temperature. Hence the tool can locate the sun from other forms of stars. HR diagrams outline data such as temperature and luminosity or energy. However, star distance from the Erath is not a type of data represented in the charts.
Explanation:
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They are said to be directly related.
a) directly related.
This is Charles' Law.
Explanation:
We have,
Semimajor axis is 
It is required to find the orbital period of a dwarf planet. Let T is time period. The relation between the time period and the semi major axis is given by Kepler's third law. Its mathematical form is given by :

G is universal gravitational constant
M is solar mass
Plugging all the values,

Since,

So, the orbital period of a dwarf planet is 138.52 years.
Answer:
a An increase in the speed will lower the internal pressure
Explanation:
Bernoulli's fluid formula

where
P = Pressure
ρ = Density of fluid
g = Acceleration due to gravity
h = Height
v = Velocity of fluid
If there is no change in height then we get

According to the Bernoulli's principle when the speed of the fluid is larger in a region of streamline flow the pressure is smaller in that region. From the above equation it can be seen that increase in speed should simultaneously reduce pressure in order for their sum to be constant.