Velocity = (displacement) / (time)
Displacement = straight-line distance between start-point and end-point
If you stop at the same point you started from, then
your displacement for the trip is zero, and your average
velocity is also zero.
Answer:
An annular Solar Eclipse
Explanation:
Solar eclipse is an event that occurs naturally on Earth when the moon in its orbit is positioned between the Earth and the Sun.Solar Eclipse can be total ,partial or annular.In the total solar eclipse, the moon completely covers the sun where as in the annular solar eclipse the moon covers the center of the Sun leaving outer edges of the Sun to be visible forming the<em> ring of fire.</em>In partial solar eclipse the Earth moves through the lunar penumbra as the moon moves between Earth and Sun.The moon blocks only some parts of the solar disk.Annular solar eclipse happens during new moon and the moon is at its farthest position from the Earth called Apogee.
Let us consider two bodies having masses m and m' respectively.
Let they are separated by a distance of r from each other.
As per the Newtons law of gravitation ,the gravitational force between two bodies is given as - 
where G is the gravitational force constant.
From the above we see that F ∝ mm' and 
Let the orbital radius of planet A is 
= r and mass of planet is 
.
Let the mass of central star is m .
Hence the gravitational force for planet A is 
For planet B the orbital radius 
and mass 
Hence the gravitational force 
![f_{2} =G\frac{m*3m_{1} }{[2r_{1}] ^{2} }](https://tex.z-dn.net/?f=f_%7B2%7D%20%3DG%5Cfrac%7Bm%2A3m_%7B1%7D%20%7D%7B%5B2r_%7B1%7D%5D%20%5E%7B2%7D%20%7D)
Hence the ratio is 
[ ans]
<h2>Snow starts to move down the mountain </h2>
The energy which is due to position is potential energy. So when the snow is lying on the mountain. It possess potential energy but when suddenly, it starts to move down the mountain, the potential energy is converted into the kinetic energy. Yet some force is exerting on the snow to stop the smooth flow of snow through mountains.
This example of frictional force may be due to presence of rough surface or stones. Generally, there are four types of friction as static, rolling, sliding and fluid friction. Though in this case when snow is lying it possess static friction, when flows then it possesses sliding and fluid friction both.
The equation to use is v=fλ where v is the speed of light, f is the frequency, i.e. the rate at which they vibrate, and λ is the wavelength in meters.
Rearrange the above equation and you get f=v/λ. So the answer is f=300000000/0.001 or 300GHz.
