Classical Physics
Why can you touch things?
What is an atom made of?
An atom is made from an electron, a proton, and a neutron.
Are neutrons and protons sub-atomic particles?
The answer is that they are. They are both smaller than atoms.
What is the theory behind the expansion of space?
Many people believe that dark energy is the reason for the expansion of space, though with little evidence to support their claims.
Do electrons orbit the nucleus (i.e., the protons and neutrons) of an atom?
No, they don't. Many people thought they did, but they simply do not. It is impossible for them to do so, for if they did, they would lose energy and crash into the protons, which they are attracted to.
Instead, electrons pop in and out of existence around protons. They also have certain probabilities of appearing, which are called electron clouds.
The movement of what creates a magnetic field?
Electrons do. When electrons move, either in an atom or through a wire, this creates a magnetic field.
Electromagnets work by running current through a coiled wire, which creates a magnetic field.
A permanent magnet works by exploiting free electrons in metals, making them spin and creating a magnetic field.
What causes an ion?
The gain or loss of an electron. For instance, if a hydrogen atom gains an electron, it becomes H- (1 proton + -2 electrons = -1 charge)
Are atoms mostly empty space?
Yes. There is so much space in between the components of the atom. Most of the mass comes from, actually, the energy from the atom - through E=MC^2
What does the equation E=MC^2 mean?
Is empty space empty?
No. There are always excitation in the quantum field. We even have things called virtual particles - particles which come and come out of existence faster than your brain can command you to blink.
What is the weakest fundamental force in the entire universe?
The weakest is gravity. While you may think gravity is extremely strong, that is only because it has nearly infinite range. However, on the atomic scale, gravity isn't even measurable. We can't even tell if gravity exists or not in the world of atoms - it's that insignificant.
What does the Law of Conservation of Mass mean?
The law of conservation of mass mandates that, in a chemical reaction, no mass will be lost.
What are protons and neutrons made of?
Protons and neutrons are both made of different combinations of quarks.
Why do we think dark matter (matter we can't see, touch, smell, etc.) exists?
Because there are inconsistencies with our equations. The equation for gravity involves mass. Considering the mass of the Milky Way galaxy, the gravity would need hundreds times more mass than we know of in our galaxy. Therefore, we think there is more mass out there, that we can't see.
Can you predict the spin of an electron?
You cannot. Due to quantum mechanics, you cannot possibly ever know, in advance, what the spin of an electron is. It is even said that quantum spin is the coin flipper for the quantum world - it is true randomness.
Do some forces not exist?
Some forces do not exist, because they do not exist from every reference point. For instance, the electric field and the magnetic field do not exist from all points, but when we combine them (i.e., the electromagnetic field), they do.
What determines the type of element an atom is?
The determiner is the amount of protons an atom has. It is just that.
What force keeps the protons from repelling each other?
The force which overcomes the electromagnetic repulsion in groups of protons is the strong force (along with the neutrons which glue them together via the strong force).
What travels at the fastest speed, from every reference point, always?
Light - or any other massless particle. Light always travels at light speed, but it also travels at that speed from every reference point. It is also impossible for light to not go at light speed. Light only appears to go slower in water because it has to move around, not because it is going slower.
Additionally, since the faster you go the speed of light, the more time slows down. So, theoretically, if you were going at light speed, time would freeze for you.
What is the cause of quantum particles?
The excitation in quantum fields create particles. For instance, if the electron field is excited, an electron appears in the universe. What we experience as waves are just oscillations in these waves. All matter is the cause of these excitations.
What is difference between gravity in classical physics and the gravity in relativity?
The gravity in classical physics is viewed as a force; however, the gravity in relativity is viewed as something that stretches space and time so that an object's future is bent to go onto the ground (literally).
What determines the isotope of an element?
The amount of neutrons in an atom determine the isotope of an element.
What is an electron made of (this may be easy based off of the other questions you've answered)?
Electrons aren't made of anything. They exist because of quantum field excitation. They are point particles, which means that they have zero dimensions.
If the universe is hyperbolic (one with negative curvature) and you constructed a right triangle light years long, what would the angles add up to (or be more than)? Hint: a spherical universe would have triangles that add up to more than 180 degrees.
A triangle in the aforementioned universe would be one that added up to less than 180 degrees.
What is the cause of quantum particles?
The excitation in quantum fields create particles. For instance, if the electron field is excited, an electron appears in the universe. What we experience as waves are just oscillations in these waves. All matter is the cause of these excitations.