Answer:
d- Earth revolves around the sun.
Explanation:
Earth rotation can be defined as the amount of time taken by planet earth to complete its spinning movement on its axis.
This ultimately implies that, the rotation of earth refers to the time taken by earth to rotate once on its axis. One spinning movement of the earth on its axis takes approximately 24 hours to complete with respect to the sun.
On the other hand, earth revolution can be defined as a complete trip along a path around the sun. This path is known as an orbit and it typically takes the Earth 365¼ days to complete it's journey around the Sun.
When a constellation (stars) changes its position in the sky, at the same time of the evening and over a period of several weeks; it ultimately implies or is an evidence that Earth revolves around the sun.
Answer:
Hello your question is incomplete hence I will give you a general answer on how A van de Graaff generator works
answer :
If the electrons falls through a PD of 150mV the electron will gain energy of 150MeV
Explanation:
when a Van de Graff generator is used to accelerate an electron through a PD ( potential difference ) of any value the particle ( electron ) the electron will gain energy ( eV ) which is is equivalent in value of the PD it accelerated through
hence if the electrons falls through a PD of 150mV the electron will gain energy of 150MeV
Using the Universal Gratitation Law, we have:
Again applying the formula in the new situation, comes:
Number 4If you notice any mistake in my english, please let me know, because i am not native.
22.5 J
Explanation:
Given:
x = 3 m
The spring potential energy 
is
Answer:
The number density of the gas in container A is twice the number density of the gas in container B.
Explanation:
Here we have
P·V =n·R·T
n = P·V/(RT)
Therefore since V₁ = V₂ and T₁ = T₂
n₁ = P₁V₁/(RT₁)
n₂ = P₂V₂/(RT₂)
P₁ = 4 atm
P₂ = 2 atm
n₁ = 4V₁/(RT₁)
n₂ =2·V₁/(RT₁)
∴ n₁ = 2 × n₂
Therefore, the number of moles in container A is two times that in container B and the number density of the gas in container A is two times the number density in container B.
This can be shown based on the fact that the pressure of the container is due to the collision of the gas molecules on the walls of the container, with a kinetic energy that is dependent on temperature and mass, and since the temperature is constant, then the mass of container B is twice that of A and therefore, the number density of container A is twice that of B.
