Reserves might last 53.3 years.
Earth’s mineral resources:
Answer:
h~=371.26m
Explanation:
when an object falls we use the equations of accelerated motion. There is only one that gives distance.

Since we have no initial velocity (started from rest) we can get rid of the (ut) term
where a we substitute g (gravitational acceleration, constant for given heights and almost 9.81m/s^2).

Answer:
It is said that the negative charge moves because the electrons in the atoms of any object are taken or given to the atoms of another object.
Explanation:
The atom is made up of protons, electrons and neutrons. The number of protons is exactly the same to the number of electrons for a certain element. For example, hydrogen: it has a proton, and therefore, an electron.
The electron has a negative charge. The proton has a positive charge. And the neutron has no charge, so it is neutral. While the atom has the same number of protons and electrons, it will not be electrically charged.
An example of how a charge exchange occurs between two objects is through the case of rubbing. This makes the atoms of the two objects close enough that there is an electron transfer, causing any of the objects to gain or lose electrons as a consequence of each other interaction. In the case of transferring electrons, the atom will have a greater number of protons, so it will be positively charged. When the atom receive electrons, it will have a greater number of electrons, so it will be negatively charged.
Therefore, since it is the electrons that move from one atom to another, then it is the negative charge that moves (<em>characterized by the electrons</em>) and not the positive charge (<em>characterized by the protons</em>).
Answer:
12 Neutrons
Explanation:
So the mass of sodium is 22.990. You round it up to get 23(as stated in the problem). So, <em>what exactly is atomic mass?</em>
Atomic Mass is the total amount of neutrons and protons added up to form a total mass. So when you subtract 23-11 you get 12 Neutrons.
<u>Tip: </u>Don't know if you need this but-
The neutrons and protons are typically close in number (unless it's an isotope). So say that you subtract and the numbers of protons and neutrons aren't close at all. Well if that's the case, it's probably wrong.
hope this helps!!
Friction is directly related to air particles.
When we say that friction is high, it means that you're colliding with lots of air particles, and hence you can't speed up as easily.
Thus, the more air particles you encounter, the higher the friction.
The faster you go, the more particles you will encounter in a given time; hence at higher speeds, the friction is higher.