Silly supersonic question

[dilbert]

ATG said:

dilbert said:

Eric Mc said:

There will always be finer points to make.

But the important thing is that the speed of light can vary.

The OP obviously lacked even the most basic understanding of the difference between the speed of sound and the speed of light.

Some of the posts on this thread would bamboozle Stephen Hawking.

The important thing, is that to the casual observer, the speed of light can appear to vary.
The more important thing, is that to the critical observer, the speed of light does not change.

Edited by dilbert on Friday 23 July 19:58

The speed of the propogation of electromagnetic waves does change ... em wave prop being a perfectly reasonable definition of the "speed of light". "c", the constant that turns up in special relativity, is known as the "speed of light" ... but is primarily a property of space time rather than light. Thus we need to be careful about what we mean when we see "speed of light".

See or say?

I didn't really want the crown TBH!

I've already got something better out of this thread which is the Feynman lectures. I've watched three of them already. The MIT physics lectures are pretty cool too.
Thanks for those.

Edited by dilbert on Friday 23 July 21:31

[Eric Mc]

Mr E said:

Eric Mc said:

One of the first things I ever learned in science.

I learnt to check the bunsun was off before reaching over it.

That was the second thing

[BMWChris]

Simpo Two said:

BMWChris said:

Do radio signals travel at the speed of sound?

Eric Mc said:

The OP obviously lacked even the most basic understanding of the difference between the speed of sound and the speed of light

Eric was,as ever, simply being factual. It's a fundamental mistake, but people just can't bear to be told they're ignorant.

760 miles an hour
vs
186,000 miles per second

Somewhere between general knowledge and 'O' level physics. And so now you know Chris

Edited by Simpo Two on Friday 23 July 20:08

"Ignorant" seems a bit strong.

The key part is the "do" in the original question and to note that I had referred to it as a "silly question" in the title. I wasn't thinking that they do, I was asking if they did.

I know a lot of stuff that most other people don't know, but I wouldn't call them "ignorant" just because they don't know it. I am aware that there is a lot more that I don't know than I do and I don't have a problem with it. Consequently I don't need to make sure I let everybody know how clever I am. I guess it’s a self confidence thing.

We didn't do O levels when I was at school but I did learn an interesting lesson about people who need to put others down to mask their own deficiencies. For what its worth I did get an A (no A* in my day) at GCSE Physics but it never really floated my boat and consequently I didn't really pay attention or continue with it after 16.

I had an interesting (to me) question that popped in my mind and I asked purely for amusement. I knew that there must be a very simple answer and, had I thought about it, I would almost certainly have concluded that the radio waves must go much faster than the plane.

I don't want to fall out with you John, you took lovely photographs for us, but I think yourself and Eric should have a think.

[Eric Mc]

I certainly didn't refer to you as "ignorant",

But I was surprised that someone, even in the course of general "growing up", wouldn''t have picked up on the basic difference between the nature of sound compared to the nature of light.

I'm sure I was told the difference by my mum (who left school at 14 back in 1938). And I amsure the question would have arisen when watching a thunderstorm in action. That is often the most obvious example where the difference shows up. The standard question would be, "Why do we see the flash first and then hear the thunder a few seconds later?".

Did you NEVER ask that question as a child?

[BMWChris]

Of course I knew from a very young age that sound travels much slower than light. The only thing I didn't know was that radio waves travel at the speed of light.

[Eric Mc]

Aha - you should have watched an episode of Captain Scarlet - where he heard Big Ben chime 13 times. It was all explained in that episode.


http://en.wikipedia.org/wiki/Big_Ben_Strikes_Again


There were some advantages growing up in the 1960s.