The kinetic energy of the electron is

where

is the mass of the electron and v its speed. Since we know the value of the kinetic energy,

, we can find the value of the speed v:
Answer:
Explanation:
Gravitational Potential Energy at earth surface 
Gravitational Potential Energy at height h is 
Energy required to lift the satellite 

Now Energy required to orbit around the earth



(given)




(b)For greater height
is greater than 
thus energy to lift the satellite is more than orbiting around earth
Answer:
Explanation:
Let the angle between the first polariser and the second polariser axis is θ.
By using of law of Malus
(a)
Let the intensity of light coming out from the first polariser is I'
.... (1)
Now the angle between the transmission axis of the second and the third polariser is 90 - θ. Let the intensity of light coming out from the third polariser is I''.
By the law of Malus

So,



(b)
Now differentiate with respect to θ.


Answer:
You are doing this wrong. Make sure that if you have 2 rows and on the top it has pounds then on the second bottom row you also have pounds so that they cancel each other out.
Explanation:
FALSE <span>Only electromagnetic </span>waves<span> can </span>travel through a vacuum<span>; mechanical </span>waves<span> such as sound </span>waves<span> require a particle-interaction to transport their energy. There are no particles in a </span>vacuum<span>. </span>Waves<span> are either </span>longitudinal<span> or transverse.
</span>Hoped i helped :):)