Why are gravitational, electromagnetic, and nuclear forces often called fundamental or basic forces??????????

Answer 1

coz these are the primary forces used in all of physics..
all other forces emanate from these forces.
These are called the fundamental forces because they can be found down to the atomic level of physics. Every single atom contains/ shows evidence of these forces..
However in the near future, with further development in quantum physics, the fundamental forces may change, with other forces being discovered in the sub-atomic level.

Answer 2

If you break down every thing you know to just the very basic properties you will find that almost everything (there are some weird Quantum effects) can be explained by these four forces. So by understanding the properties and effects of these forces you can make very accurate predictions on experiment.
For example it is like knowing how to add, from which comes multiplication (2*5 = 5+5), then you can describe powers (5^2 = 5*5 = 5+5+5+5+5), infinite power series (not writing that example out, lol), geometric series, Complex Variable Analysis, vectors, tensor fields, etc which are more complicated but are results are of the basic "force" of adding.

Answer 3

Because that's what they are. The four fundamental forces currently known are gravity, electromagnetism, and the strong and weak nuclear force.

There is active research in physics to "unify" all the forces into a "grand unified" force from which all fundamental forces derive.

Answer 4

Read my answer to one of your other similar questions. These answers won't alleviate the need for you to study the forces to learn about them.