Steven Mark`s TPU

[PulsedPower]

@BEP

Now for the reality of a car crash:
The two cars are LEM (longitudinal) cars. They are both travelling at 50 kph. When they hit, the damage done is the same as if each separately hit a brick wall at 200 kph or (A+B)2

The 2 car collision was a poor analogy.  2 cars of equal but opposite velocity, equal mass and equal structural rigidity and strength behave the same in collision whether it is head on or with a brick wall interposed between them. The point of collision is stationary while the 2 cars crumple identically on either side of the point of impact. If the cars have differing strength and or structural rigidity the point of collision moves in the direction of the stronger car meaning that the effective collision velocity for the weaker car is higher. It will never be 100km/h as even a vehicle with infinite strength and rigidity is still decellerating during the collision. For 2 vehicles of differing mass, the lighter vehicle will see a higher collision velocity as the heavier vehicle decellerates less. In the extreme case of one vehicle having infinite mass and rigidity the other vehicle will have to absorb the entire 100km/h collision for less than infinite rigidity the effective collision speed will be less than 100km/h

To better visualise this, a vehicle hitting a brick wall at 100km/h is identical to a brick wall and attached planet travelling at 50 km/h being hit by a vehicle travelling at 50 km/h in the opposite direction. The car hits wall at 50km/h decellerates to 0km/h then continues to decellerate to -50km/h (the brick wall speed is unchanged)

The energy of a moving object is 1/2mv^2 , the damage done to a vehicle is this energy doing work on the vehicle.  Two vehicles of the same mass and speed have the same energy, if 2 vehicles approaching at the same speed had 2x the effective speed at collision then the collision energy would be 4x the single vehicle energy and double the actual energy ( 2 x 1/2mv^2) energy making car crashes an overunity event.

The effective speed at collision is different from the apparent speed, I probably didn't do a good job of explaining this but it is such a common misconception that myth busters should run it..

[turbo]

It all sounds familiar but i did not see the inertia come into play.

If the planet would stop rotating, the atmosphere would still move on for a short while due to inertia.
If we create a rotating magnetic field using sines/pulses it is quite different then when we set a static field in motion.
That is, not 100% correct because we only create the apperance of a rotating magnetic field at some distance with respect to the used magnet/coils.
We can say the field only varies in amplitute in a rotary fashion and that at a specific distance this will look similar as to a real rotataing magfield.

M.

[PulsedPower]

@-Marco-

It all sounds familiar but i did not see the inertia come into play.

If the planet would stop rotating, the atmosphere would still move on for a short while due to inertia.

I guess you were referring to my post about the collision of 2 vehicles and not a post about 2 EM waves passing in a transmission line, if not disregard this post.

Anyway When a vehicle accelerates it accellerates the planet a minute amount in the opposite direction, the same when it decellerates, a vehicle crashing into a wall doesn't stop the planet it merely slows it slightly as the vehicle accellerates to the planets speed and yes the atmosphere should lag in speed slightly, the effect is so minute as to be negligable due the very much greater mass of the planet.

My post was written in terms of Kinetic energy, Inertia is not energy just like Volts and Amps are not energy, Inertia is useful for calculating forces. An ommission in my previous post was that if 2 vehicles of identical mass and opposite velocity collide but they have different strengths the final velocity of both vehicles will be the same due to conservation of inertia, but the weaker vehicle will have absorbed the most energy and the collision point will be displaced toward the weaker vehicle.

I appologose for getting a bit OT, the transmission line stuff brings back memories

[pese]

2 very interesting pdf?s ,
that i find in my collection again.
must not longer undercovered..

[pese]

Dupr?  (in german )
sehr interessante Lekt?re,  die
es icher Wert ist beachtet zu werden.
Must be read . Magnet field in DC current circles