How did we come to know about nuclear force if we cannot even see the atoms or atomic nucleus?
What is a nuclear force?
The nuclear force is, as you may already know, the force between protons and neutrons all together in an atomic nucleus. Other facts you may know about this force is that it is the strongest force in nature, but its range is incredibly tiny.
Why is it important?
On the scale of a nucleus, you may imagine simplistically, there are protons and neutrons. The protons repel each other by electromagnetic force. Right? So even scientists thought why aren’t the protons flying apart and what is keeping them in place in nucleus so close to each other?
Something was keeping the protons huddled close together, right? Because we don’t see atomic nucleus disintegrating all the time and due to in part of the stability of the nucleus and the atoms, we are here studying and wondering about them.
Now, on larger scales, we can see apples falling (thanks, Newton!) and planets revolving around the sun in elliptical orbits which can make us aware of gravity. Or we can bring two magnets together and observe the interaction between the two of them. They will either attract or repel each other. We can also run electric current and study its effects on an adjacent parallel wire. Or simply that we do not fall into the earth and can safely sit in our chair. This makes us aware of the electromagnetic force.
These two forces can be observed on our day to day large scales. But the nuclear force is said to act only on tiny scales of fractions of femtometer. (Which is 100000 times smaller than the size of an atom!). This distance is so small that our human brains have a hard time imagining it. And the important fact about nucleus or even atoms is that we cannot directly see them. Optical and electron microscopes just cannot do the job.
So, if we cannot see the atom, let alone the nucleus, then how can you come to know about the nuclear force for sure? What observations and deductions do you need to come to before you can strongly say that yes, indeed, there is some nuclear force? What experiments can you perform to conclusively observe the existence of the nuclear forces?
Extra question: What about the weak nuclear force?
Let us know in the comments below your thoughts and answers. Or email us your ideas at firstname.lastname@example.org.