I have started reading The Feynman Lectures in Physics. Overall there are three volumes to collection. They were created from a two year course in physics given by Richard P. Feynman, a professor at Caltech and a Physics Nobel Prize winner. I am finding the books not only refreshing (they have almost no equations) but also entertaining and so very useful. I am learning physics over again in some areas and learning truths I never really understood before.
I am current on chapter 17 (of 44 in this volume) and have bee making notes. In the spirit of sharing and of consolodation for my own sake, here some things I now know.
On Atoms
An atom is about 1 or 2 Angstroms across in size. An angstrom is 0.000000000 1 metres and this makes atoms comparable in size to one hundredth of the wavelength of light.
If you made an atom the size of a room then the nucleus, containing the protons and neutrons would be a mere speck of dust barely visible in the centre.
If an apple were magnified to the size of the Earth then the atoms in the apple would now be the size of the original apple!
You can burn a diamond in air.
CO (Carbon Monoxide) is essentially a picture of itself.
On the Fundamentals
Think of a game of chess. you can watch the game and you might grasp a few of the rules. You might see that Bishops move diagonally or that pawns move only one step. You will however not necessarily be able to play just by watching. Why one player makes a move or another responds will seem a mystery. This is akin to the laws of nature, i.e. physics. We can know the rules (gravity, kinematics etc) but not therefore how to play.
Some of greatest moment sin science have been when two or more seemingly unrealted topics are shown to be related and intertwined. some examples are quantum mechanics and chesmistry; electricity, magnetism and light; heat, temperature and mechanics.
Helium was discovered on the Sun before it was found on Earth. This is why is got its name; Helois was the Roman god of the Sun.
6 fundamental things are always conserved. That is to say that these things are never created or destoyed spontaneously but simply moved around the universe. These conservation laws tell us a lot about how nature works. The six conserved quanities are energy, linear momentum, angular momentum, baryons, leptons and electric charge.
There is enough energy is 1000 litres of running water to power the entire of the United States. It is up to physicists to figure out how to liberate it so that the world can be freed of its need for energy. It can be done!
On Time and Distance
Does time exist on an ever shorter scale? A day contains 24 hours, which in turn contains 60 minutes of 60 seconds a piece. How far down can we go and does it make sense to speak of times which cannot sensibly be thought about?
We can use carbon dating to pin something down to being more than 100,000 years old, ut not much further. Uranium on the other hand can reliably date things back for billions of years, so long as there is rock there that has remained unchanged for as long. The oldest rock on the Earth is over 4 billion years old!
Atomic clocks will soon be accurate to within one second in the age of the entire universe.
On Gravity
If you fire a bullet it falls at the same rate as anything else but obviously moves a very long way across the surface of the Earth in the same time. If you could fire a bullet at 5,000 miles per second then it would never hit the floor as the Earthb would curve away benath it as fast as it could move. The bullet would be in orbit.
The tide come sin 50 minutes earlier each day.
Due to the width of the Earth’s orbit around the Sun, the light travel time from planets like, Mars, Jupiter, Saturn etc varies by almost half an hour. This fairly long period of time has astronomers very confused in the 17th century when their predictions for the orbiting periods of Jupiter’s moons kept appearing to be wrong by anything up to half an hour. Eventually this led them to thi k that light may have a finite speed and so the first estimates for the speed of light, c, were made in 1656.
Thats all for now…
