What are the four fundamental forces of nature?

Answer 1

The four forces affecting matter are (in order of increasing strength):

1. Gravitational Force

2. Electromagnetic Force

3. Weak Nuclear Force

4. Strong Nuclear Force

Gravity holds macroscopic matter together.

Electromagnetic force prevents atoms and molecules from getting too close, or from passing through each other.

The weak force is why molecules form.

The strong force keeps an atom's nucleus together.

Answer 2

The four forces govern the behavior of subatomic particles are the only four forces that we know about in our Universe: the strong nuclear force, the electro-magnetic force, the weak force, and gravity.

Answer 3

The four fundamental forces (or interactions) of the Universe, in (sort of)1 increasing strength, are:

Gravity: Force of attraction between objects with mass. The strength of the gravitational force is proportional to the mass of the physical bodies and inversely proportional to the square of the distance, and is the only force that works over long distances.

Weak interaction: Also called the weak nuclear force; it is caused by the exchange of W and Z bosons, the best known effect being beta decay.

Electromagnetism: The interaction between particles that have electric charges and is found in electric and magnetic fields.

Strong interaction: Also called binding energy/strong nuclear force; mediated by gluons, it holds quarks together to form protons and neutrons. Residual binding energy, also called the nuclear force, i.e.without the word "strong", holds protons and neutrons together in the atomic nucleus.

1These are listed in decreasing order of perceived strength, however, strength is also an inverse function of distance, so the stated order could be interpreted otherwise. For instance, one could say that gravity is the strongest force because it works over the greatest distance, but within the confines of the nucleus, the stated order is generally2 as stated.

2However, the exception to this is that the Strong Interaction has a steeper inverse distance response than Electromagnetism. As a result, in nuclei of atomic number 82 (lead) and smaller, the Strong Interaction wins out, but for nuclei of atomic number 83 (bismuth) and larger, Electromagnetism starts to overcome the Strong Interaction, making all of the larger nuclei unstable3, i.e. radioactive.

3Yes, there are nuclei smaller than iron which are also unstable. Technetium and promethium, while smaller than lead, have no stable isotopes. Carbon-12 is stable, while carbon-14 is not. These are just examples. This instability, even with the Strong Interaction being more powerful than Electromagnetism, is due to the Weak Interaction, along with the possibility that every isotope with atomic number greater than 40 (zirconium) is theoretically possible of spontaneous fission. (Although some have not yet be observed.)

Answer 4

The four forces that hold atoms together are gravity electromagnetic, and a strong and weak force. An electromagnetic force is a force that combines the effects of electrical charge and magnetism.

Answer 5

There are four main forces in nature, electromagnetism, gravity, weak nuclear and strong nuclear. Gravity doesn't play a part in holding an electron in place, as the masses are two small.

Electromagnetism attracts the electron to the nucleus as it is a positive centre and the electron is negative.

Strong nuclear force holds the nucleus together.

Weak nuclear force is the one that keeps the electron away from the nucleus.

Answer 6

Gravitational, Strong Nuclear, Weak Nuclear, and Electromagnetic.