# Search Results

1. Post

### B Second law of thermodynamics

Is the building an isolated system?
Post by: Dale, May 29, 2017 at 6:06 AM in forum: General Physics
2. Post

### I potential inside a charged conductor.

No, this is not correct. The work done would be different. Go back to the definition of work and check if something is different for the two paths.
Post by: Dale, May 29, 2017 at 5:38 AM in forum: General Physics
3. Post

### B Mining of He-3 on the Moon?

I am with @Drakkith on this. What do you mean "negative effects"? The moon isn't alive so you can't make it sick.
Post by: Dale, May 28, 2017 at 6:33 PM in forum: General Physics
4. Post

### I Proper (and coordinate) times re the Twin paradox

No, the "same physical location" implies a frame which identifies locations and determines if they are the same or not. However, what you can say...
Post by: Dale, May 28, 2017 at 2:25 PM in forum: Special and General Relativity
5. Post

### I Speed of wave in a string w.r.t. which reference frame

How was the equation derived? What assumptions were made in the derivation of the equation?
Post by: Dale, May 28, 2017 at 12:53 PM in forum: General Physics
6. Post

### I How do we decide dimension of motion?

I am in the "it doesn't matter" camp. If you want you can use Newtonian mechanics and analyze it using 2 variables. If you want you can use...
Post by: Dale, May 28, 2017 at 12:49 PM in forum: General Physics
7. Post

### I What is Energy... Really?

it could all be used as long as your cold reservoir is at absolute 0.
Post by: Dale, May 27, 2017 at 10:58 PM in forum: General Physics
8. Post

### I Proper (and coordinate) times re the Twin paradox

Yes Yes Yes. The mistake you are making is thinking that proper time is a relationship between two events. It is not. It is a property of a...
Post by: Dale, May 27, 2017 at 8:32 AM in forum: Special and General Relativity
9. Post

### B Ball bouncing on a planet (no atmosphere) follow up questions

The gravitational force of the ball on the planet. Use the center of momentum frame. The combined momentum is zero at all times. Again, do you...
Post by: Dale, May 27, 2017 at 7:18 AM in forum: General Physics
10. Post

### I potential inside a charged conductor.

Yes, if they are just outside then they are not necessarily equipotential. Think about the excellent analogy from @rumborak, but make it a little...
Post by: Dale, May 27, 2017 at 7:15 AM in forum: General Physics
11. Post

### I potential inside a charged conductor.

Just inside the surface is equipotential, but just outside the surface is not equipotential. I am unsure about actually on the surface.
Post by: Dale, May 27, 2017 at 6:57 AM in forum: General Physics
12. Post

### I potential inside a charged conductor.

Then they are not equipotential, I believe.
Post by: Dale, May 27, 2017 at 6:48 AM in forum: General Physics
13. Post

### B Ball bouncing on a planet (no atmosphere) follow up questions

The answer is that it depends on the reference frame. Energy is conserved in all frames, but not transferred in all frames. In particular, in the...
Post by: Dale, May 27, 2017 at 6:40 AM in forum: General Physics
14. Post

### B Ball bouncing on a planet (no atmosphere) follow up questions

I don't think that is correct. If each collision is perfectly elastic then the ball will keep on bouncing at the same height forever. This is...
Post by: Dale, May 27, 2017 at 6:34 AM in forum: General Physics
15. Post

### I potential inside a charged conductor.

The drawing is not quite clear. Are A and Q inside the conductor or outside?
Post by: Dale, May 27, 2017 at 6:28 AM in forum: General Physics
16. Post

### I Special Relatively Conundrum

Excellent problem! Definitely a little on the macabre side
Post by: Dale, May 26, 2017 at 5:46 PM in forum: Special and General Relativity
17. Post

### I Special Relatively Conundrum

No, they do not. You need to use the relativistic velocity addition formula. You need to use relativistic velocity addition
Post by: Dale, May 26, 2017 at 5:01 PM in forum: Special and General Relativity
18. Post

### I Special Relatively Conundrum

Yes. But the direction the marble rolls does not depend only on the orientation.
Post by: Dale, May 26, 2017 at 1:41 PM in forum: Special and General Relativity
19. Post

### I Special Relatively Conundrum

The orientation is not invariant. There is nothing wrong with two reference frames disagreeing about the orientation.
Post by: Dale, May 26, 2017 at 12:25 PM in forum: Special and General Relativity