E=mc2

[xoggoth]

Hang on a minute! C is a constant! So how can it be true? In what units is it true? There is no relationship between definitions of mass and energy in any system so if E=mC^2 in any of them it must be coincidence. E=km maybe. Bleedin obvious that is! My granny could have come up with that!

[Jabberwocky]

c is m/s and mass is kg say, so m c^2 is kg m^2/s^2. Now force is mass times acceleration according to Newton 2 which is kg m/s^2, so force times distance which is work and so energy is kg m^2/s^2 so the units match.

I will explain the correspondence between the curvature of space time and gravity shortly.

[SupremeSpod]

c is m/s and mass is kg say, so m c^2 is kg m^2/s^2. Now force is mass times acceleration according to Newton 2 which is kg m/s^2, so force times distance which is work and so energy is kg m^2/s^2 so the units match.

I will explain the correspondence between the curvature of space time and gravity shortly.

So, If I drive at you at a constant speed, you won't feel a thing...

[xoggoth]

The gram, second and meter are arbitrary units, measurements from some dead French tart's anatomy I daresay. Yes, I know the joule is defined in terms of these basic units, I am (or was) a chemical engineer. But how the energy by total conversion of one gram comes out to exactly C^2 joules, I have no idea. I think AE made it up as an April fool's joke. As nobody can actually acheive a total conversion who can check?

[Jabberwocky]

You can check. Pop a thermo-nuclear device into your rucksack and make a cosmic mushroom.

[GiGo]

So, If I drive at you at a constant speed, you won't feel a thing...

It's not the driving but the collision: transfer of momentum mv in time delta t.

http://theory.uwinnipeg.ca/physics/mom/node2.html

[GiGo]

fundamental formulas

I like Euler's formula :

e^(i pi) + 1 = 0

This links the 5 fundamental constants in mathematics : e, i, pi, 0 and 1.

[PerlOfWisdom]

I don't - it's rubbish

[Churchill]

It's not the driving but the collision: transfer of momentum mv in time delta t.

http://theory.uwinnipeg.ca/physics/mom/node2.html

So, if a fly travelling due south hits a car travelling due north, the fly changes direction from South to North. Therefore the fly must rapidly decellerate and then accellerate in the opposite direction. This means that the fly at one stage must be stationary and as the car is attached to the fly's bollox, the car is stationary also. Ergo, a fly can stop a car.

[threaded]

I prefer: e^(i pi) = -1