Hopetoun Falls, Beech Forest, near Otway National Park, Victoria, Australia.
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We can show a few physicsy examples.
This is an example of applied physics---of course, pulleys were invented long before their physics was understood: i.e., before their action was understood in terms of basic physical law.
A magnet (which is an electric current) creates a magnetic field and and the field exerts a force.
Here on iron filings.
But the same basic idea of turning out gas expansion energy into mechanical and then electrical energy is behing modern steam turbines that operate in all thermo and nuclear power plants.
In lasers, the particles of light---the photons are quasi-clones of each other and that gives laser beams many of their special properties including their tight beaming.
Ordinarily you don't see the beam itself, since the laser light isn't heading to your eye.
In this image, the air must be reflecting light that the photograph is sensitive to.
In the old days, I'd have student who smoked puff smoke into a laser beam to reflect some light randomly in all directions including to the eyes of the observers.
But physics sort of ate astronomy.
But astronomy is still the Queen of the sciences.
Here's an image that shows that looking far away is looking long ago: billions of years into the past.
The things with points are foreground stars---star have points you know---all other things are remote galaxies. See Sedgwick & Gamble, p. 37--42 on star imaging.
Probably because 60 has a lot of whole number factors---12 of them---which makes many divisions clean.
This is why we still have 60 seconds in a minute and 60 minutes in hour.
The 24 hours in a day thing is probably Egyptian in origin.
Circa 500 BCE, the Babylonians also divided the circle into 360 degrees. they didn't tell us why. Probably because 360 has a lot of whole number factors---I let you count them.
But though we know a fair bit about their data and calculations, the Babylonians left virtually nothing of what they thought the physics of the world was.
Perhaps they didn't think very much about that.
They did tell us a lot about what they thought.
And they knew a lot about geometry.
But if their geometry was strong, their algebra and calculus were weak.
Also they were not very experimental---they did a few experiments, but they didn't CONSISTENTLY have the idea that experimentation and detailed observation were critical ingredients of science.
Leaning Tower of Pisa No one's ever forgotten the ball dropping affair.
Many of his ideas were incorporated into Newtonian physics.
Up until circa 1900, people believed that it was perhaps exactly true.
Since then, of course, we have learnt that is not the case.
Still we believe that it is the exactly true limit of more advanced theories for the world of everyday objects up to the world of galaxies or a bit larger, down to nearly the atomic scale, and at speeds much less than that of light.
So it is still tremendously useful which is why we study it.
It's also a theory of great beauty and elegance.
I call it a true approximate theory.
Of course, since Newton's time notation and formulations have changed somewhat.
There are theories of everything or nearly everything, but they havn't yet gained acceptance.
Maybe soon or maybe never we will have TOE.
TOE would complete fundamental physics---the ultimate just-so story.
Personally, I think theory of everything is an inaccurate name.
It wouldn't be a theory of everything.
Although when a naive boy physicist, I used to think so.
But I don't think those systems are dictated absolutely by the components.
As a trivial example, chess is a set of rules---it doesn't matter what the pieces and board are made of.
Consciousness and evolution are non-trivial examples.
It's at least possible to imagine that their rules would operate in worlds with quite different physics from ours.
