| | What's the difference between "Geschwindigkeit" (German for speed)
| | and "Geschwindigkeit" (German for velocity)?
| |
| |
| | Dunno exactly.
|
| The difference is direction.
|
| And if you don't know enough English to understand the English words
for
| magnitude and direction,
|
| I do. The words you asked about were in German.

No you don't, you hallucinate distance is a scalar.

No, distance does not have a direction.

If you Google "is distance a scalar or a vector", then the first hit is

http://wiki.answers.com/Q/Is_distanc...or_or_a_scalar

Which has five answers, all of which say distance is a scalar.

The second hit is

http://www.physicsclassroom.com/class/1dkin/u1l1c.cfm

Which says "Distance is a scalar quantity".

The third hit is:

http://en.wikipedia.org/wiki/Scalar_(physics)

Which says: "The distance between two points in three-dimensional space is a
scalar".

So you are obviously wrong.

Not that you need to know much about vectors to learn SR. There are lots of
derivations of SR which don't explicitly use vectors at all; you would be
better off trying to learn SR through an approach which avoids vectors
entirely, you don't really need to know this stuff.





| you shouldn't try and learn basic vector algebra
| from books written in English. I would have thought this to be
obvious.
| There are lots of books in English on the subject.
|
|
| I first studied Vector algebra and vector calculus over 30 years ago,
and
| feel I have a pretty good understanding of the subject.

No you don't. You hallucinate distance is a scalar.


No, distance does not have a direction.

If you Google "is distance a scalar or a vector", then the first hit is

http://wiki.answers.com/Q/Is_distanc...or_or_a_scalar

Which has five answers, all of which say distance is a scalar.

The second hit is

http://www.physicsclassroom.com/class/1dkin/u1l1c.cfm

Which says "Distance is a scalar quantity".

The third hit is:

http://en.wikipedia.org/wiki/Scalar_(physics)

Which says: "The distance between two points in three-dimensional space is a
scalar".

So you are obviously wrong.


| That is why I was happy to answer your questions.

What's the difference between "Geschwindigkeit" (German for
distance/time),
a magnitude, and "Geschwindigkeit" (German for (directional
displacement)/time)
a vector?

You dunno.


No. My German isn't very good.


Not my fault if German has the same word for both and English "distance"
means a vector and a magnitude. That's why we use a minus sign in
mathematics. Distance is a vector. You only need to flip a ruler to
understand it,
the 12 appears on the left instead of the right. Minus is a "rotate 180
degrees"
unary operator. i = sqrt(-1) is a rotate 90 degrees operator. (-1 + i) is
a
vector.

Not my fault you've never understood vector algebra.


You are conflating a couple of different concepts here.

Not that it matters; I can't actually see the point or relevance of
discussing the meaning of German words in a conversation on Relativity.




| |
| |
| | What's the difference between velocity from A to B and velocity
from
B
| to
| | A?
| |
| | Hint: a minus sign.
| |
| |
| | If you say so. I can't see any reason why a particle couldn't travel
| from
| A
| | to B at a completely different speed to that which it moves from B
to
A.
|
| I do say so. Velocity is a vector and so is distance, it has direction
| too.
|
|
| Just because two things are both vectors doesn't mean that one of them
is
| neccesarily minus one times the other one.

Learn to spell, low life.
Speed is a magnitude, velocity is a vector. Distance is NECESSARILY a
vector.


No, distance does not have a direction.

If you Google "is distance a scalar or a vector", then the first hit is

http://wiki.answers.com/Q/Is_distanc...or_or_a_scalar

Which has five answers, all of which say distance is a scalar.

The second hit is

http://www.physicsclassroom.com/class/1dkin/u1l1c.cfm

Which says "Distance is a scalar quantity".

The third hit is:

http://en.wikipedia.org/wiki/Scalar_(physics)

Which says: "The distance between two points in three-dimensional space is a
scalar".

So you are obviously wrong.



So you don't believe the experimental predictions of relativity because
you necessarily don't understand what distance/time is and have a low IQ,
obviously, since you can't spell.



You *don't* need to understand German to learn SR.

You *don't* need any sophisticated mathematics, and you *don't* need to be
conversant with vector algebra.

Why don't you do as I suggest, and try learning it from a book *written in
English* that doesn't explicitly use vector algebra?