Physics are the most base of all scientific “genres” and thus you would think, be the most simple of all the Sciences. However there is a lot that can only be understood on a theoretical basis, since we cannot “view” forces as they are. Instead we view the actions and reactions that visible objects take when forces are exerted on them.
A lot of what physics focus on are how they connect the grand scheme of the laws of the universe together. Some of these laws can be bent, a lot of which seems to be founded on our own perception of them (again based on indirect observation). There is no escape from Physics; the atoms and molecules in your body stay together because that's what the laws tell them to do.
Before Isaac Newton, people believed that things fell to the earth simply because they did. Newton thought that there must be a reason, or force, causing the universal action of objects falling to the earth. And well, he was right. Gravity acts equally upon all objects falling simultaneously. But what does that mean exactly. We now know that different planets all have different amounts of Gravity based on their size and density. What this means that if I drop two bowling balls from the same height, they will reach the ground at the same time and the same speed. "Well, of course they will!" You're probably saying, "They are both the same size and weight as each other." Well, that may not necessarily be the case, but I'll give you a better visual: Now I have a bowling ball and a marble about the size of a cherry. I drop them and they both hit the ground at the same time and speed. "But what about feathers? They don't fall at that speed!" Yes, you're right, almost. If you were to take away air resistance or friction and place a bowling ball and a feather in a complete vacuum, you would find that they DO fall at the same rate. Another force is altering how an object behaves. Feathers are not very dense and have a large surface area that contacts with the air around it, slowing it down. A bowling ball, or even a marble or cherry, is very dense, adding an aerodynamic (that's for another time) shape allows it to further cut through the air, meaning the air slows it down very little.
Thus you can say that the forces that cause Gravity are universal.
There are a whole lot more to Physics than Gravity, in fact I've only focused on one category of the seven branches of Physics, which is Mechanics. The seven branches are: Mechanics, Thermodynamics, Vibrations and Waves, Optics (including visible light), Electromagnetism, Relativity (E=MC^2 ;{P), and Quantum Mechanics. You will notice that these are almost a spectrum as they can fade or transfer from one to another. Transferring energy depending on its quantity and form.
Every action you take and make requires Physics, uses Physics, and causes Physics. It really shouldn't be overwhelming other than perhaps in the sheer grandeur of its quantity as it surrounds you. When finding out whether Physics follows a pattern or theory in action, what you must do is experiment. And since Physics are "invisible" you have to simply see if it doesn't work enough times to narrow down the options.
Best to you!
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