Recent content by powermind

Good! I would like to be sure about your answer DaleSpam. Same example of closed vehicle. The experiment will be inside the vehicle. in case of moving: 1- The observer is in the back of the vehicle. The sound source is in the front. The observer will hear the sound after Δt1. 2- The observer is...

First, do you agree with the paragraph I referred. If the driver is in the closed vehicle with no windows no air enters from outside because the vehicle is totally closed. The outside observer sees the vehicle moving relative to him. The driver will not know he is moving. This is what the...

But I mentioned that the all windows are closed and nothing enters inside! I add you cannot see anything outside. http://jcer.com/index.php/jcj/article/viewFile/80/78 (P 532) I hope you understood my point!

If the observer and the sound source are stationary relative to the air the speed of the sound is 343m/s. But if both moves relative to the air, you said that, as I understood, the speed of the sound relative to them will be not equal 343m/s. So they can know that they are moving relative to the...

You said:

A.T, your answer will be differnet if the sound is generated inside the car which is nothing enters from outside. i.e the windows are closed?

Does this disagree with special relativity: the laws of physics are invariant in all inertial systems?

Many thanks

I am sure he cannot hear the siren because the sonic boom is more loud than siren :) It means that the speed of sound is directly proportional to the speed of its source!

Borek, this is similar to the light, is not this? The light speed is not affected by the speed of its source too.

Do you mean that the speed of the siren's sound is not affected by the siren speed?

But the speed of the siren's sound related to the outside person=The speed of the sound relative to the dirver-the speed of the car=343-343=0! I am talking about the sound which goes to the person. If this is wrong, when will the person hear the siren if you have the following: 1- The speed of...

Hi, Suppose the police car moves faster than sound's speed and runs away from the person on the street. Will the person hear the siren? Regards,

Hi, Suppose the police car moves faster than sound's speed and runs away from the person on the street. Will the person hear the siren? Regards,

A.T., unfortunately, you did not understand me. The values derived from the Lorentz transformation give you different clock depending on the position of the event in the frame O'. t = γ(t'+vx'/c^2) t the time according frame O. DaleSpam, I am talking about the time derived by the Lorentz...