Do magnets attract all metals, and is the speed of light in a water

1. May 23, 2013

x86

1. The problem statement, all variables and given/known data
Do magnets attract all metals, and is the speed of light in a water constant?

2. Relevant equations
None that I know of

3. The attempt at a solution
I would assume that magnets attract almost all metals because they have an electron sea in them and they would be attracted to the magnet.

But what about the speed of light in water? My physics teacher said that the speed of light in water depends on the medium it comes from. But I read that its always a constant value (3 *10^8m/s / 1.33)

Is it true that the speed of light in water would be different if the light came from a vacuum, compared to if the light came from say a diamond?

2. May 23, 2013

SteamKing

Staff Emeritus
3. May 24, 2013

x86

After reading those articles, it is my understanding that not all metals are attracted by magnets (like copper is repelled) and that the speed of light in water will always be constant, no matter what medium it comes from.

Can you confirm that this is correct?

4. May 24, 2013

rude man

Yes to both.

5. May 24, 2013

x86

Thank you for clearing up my confusion

6. May 24, 2013

CWatters

7. May 24, 2013