I guess the military would have done such experiments. But Ramjet is just a jet type, I couldn't find any specific info about stacking velocity.


Ok, I've gone through the wiki, doppler effect refers to the sound waves compressing as we head in their direction, causing them to appear to have a higher frequency.

But I don't think I can test this to prove either.

The word Stacking Velocity was just coined for lack of knowledge what the physics world calls this effect. Would be good if someone could drop me more keywords.

You know I began asking the TS questions, because thinking, that if I travelled on a speeding train, and jump to the front of it, I'd very soon get rammed by the train, therefore, what happen to the initial inertia while on the train? Does that mean that my moving on the train was just a temporary borrowing of the trains inertia, whereby my running on it doesn't stack?

The strange thing is, if for example, there was another train travelling at the same speed infront of that train, and I jumped, I would land smoothly on the other train without loosing much, why is that?

The answer is that, the only reason we decelerate so fast after leaving the train is the air friction and other resistance. The faster you travel, the stronger will the air friction be, which is why, you will fly backwards if you try to jump of the train.

It doesn't have to be a vacuum, in the cabin of the train itself, the air around you are travelling at the same speed as yourself, so whatever you throw in it, will have the same reaction, as if you did the same experiment on solid ground. The moment your cannon ball leaves the cabin, it will be blasted with air, such as it would at the speed of the train + the speed of the cannon ball, causing it to greatly decelerate.

However you have choosen a cannon ball, which has an aerodynamic shape, and the weight gives it more momentum, therefore the wind blast will have less effect on it. Such as what happens when you drop a marble and a feather, the marble will drop faster.

This post has been edited by TheDoer: Sep 17 2010, 10:18 AM

Ignore that post by Awakened_Angel, none of the information posted there is relevant to your question.

This post has been edited by Eventless: Sep 17 2010, 10:21 AM

Let me try.

Have you sit a car, with a fly buzzing around? When you drive at constant speed, a fly would happily buzzing around inside your car. Be it rest, or take-off, it seems to be able to fly effortlessly. But mind you, the car is traveling at constant speed, say 60km/h.

Say, as your car pass point A, the fly take-off from your dashboard and buzz around. As you drive for like 1 minute (at 60km/h, that is 1km), and pass point B, the fly return and land back on your dashboard.

To the fly, for all it knows, it is flying inside around and then return to his original location. But because the car is moving, the fly actually flew for 1km.

So, if you were to jump inside a train, you will land on the same place inside the train. But from the outside, the scenario is the same as the fly example.

This post has been edited by Aurora: Sep 18 2010, 02:05 AM