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39 minutes ago, Bazza said:

Higher than real mathematics. 

 

Did you do that knowingly or by accident?  "Complex analysis" involves imaginary numbers; "Real analysis" works strictly with real numbers and leaves out the imaginary components.

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It's official: I have completed my Master's Degree.

Another student suggested that we stop referring to a certain group of people as "anti-vaxxers" and start calling them "plague enthusiasts". 

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4.  Charges Q1 and Q2 are separated by 0.2 m, and Q1 is inside a conducting box whose nearer wall is halfway between Q1 and Q2.  Q1 = +10 nC; Q2 = -20 nC.  Does Q2 exert a force on Q1, and if so is it an attractive or repulsive force?

 

A) No force

B) Yes, and it's an attractive force

C) Yes, and it's a repulsive force

D) Yes, and while it's not very pretty it is rude to call it "repulsive"

 

EDIT: stupid emoji

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1 hour ago, Cancer said:

4.  Charges Q1 and Q2 are separated by 0.2 m, and Q1 is inside a conducting box whose nearer wall is halfway between Q1 and Q2.  Q1 = +10 nC; Q2 = -20 nC.  Does Q2 exert a force on Q1, and if so is it an attractive or repulsive force?

 

A) No force

B) Yes, and it's an attractive force

C) Yes, and it's a repulsive force

D) Yes, and while it's not very pretty it is rude to call it "repulsive"

 

EDIT: stupid emoji

 

* writes down the question for his Honors Physics unit on electric charge in a couple of weeks *

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3. Annie Mercury, intrepid explorer and physics student, finds herself pulled through a vortex and into an alternate reality. This reality has a fifth fundamental force that its residents call "qlopz". The qlopz force is always repulsive, obeys the inverse square law, is measured in units called œnua (abbreviated Œ), and obeys a law something like the Universal Gravitation equation or Coulomb's Law with a proportionality constant Ð. Surprisingly, Annie discovers that the denizens of this universe measure force in newtons and length in meters. Some things never change, I suppose.

 

During one experiment, Annie observes two objects [r] centimeters apart with qlopz values of [ql1] Œ and [ql2] Œ. Calculate the force between these two objects in terms of Ð (25Ð, ¾Ð, 2.37x10-6 Ð, etc.).  Round your answer to the nearest 0.1Ð N.

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On 2/6/2021 at 8:58 PM, Cancer said:

4.  Charges Q1 and Q2 are separated by 0.2 m, and Q1 is inside a conducting box whose nearer wall is halfway between Q1 and Q2.  Q1 = +10 nC; Q2 = -20 nC.  Does Q2 exert a force on Q1, and if so is it an attractive or repulsive force?

 

A) No force

B) Yes, and it's an attractive force

C) Yes, and it's a repulsive force

D) Yes, and while it's not very pretty it is rude to call it "repulsive"

 

EDIT: stupid emoji

 

Q1 induces a negative charge on the face of the wall closest to it and a positive charge on the opposite side of that wall. Q2 induces a larger positive charge on the face of the wall closest to it, and a correspondingly larger negative charge on the opposite side (i.e., the side closest to Q1). End result: The conducting wall has a negative charge on the side closest to Q1, which exerts an attractive electrostatic force on Q1.  The answer is B.

 

Right...?

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10 minutes ago, Pariah said:

3. Annie Mercury, intrepid explorer and physics student, finds herself pulled through a vortex and into an alternate reality. This reality has a fifth fundamental force that its residents call "qlopz". The qlopz force is always repulsive, obeys the inverse square law, is measured in units called œnua (abbreviated Œ), and obeys a law something like the Universal Gravitation equation or Coulomb's Law with a proportionality constant Ð. Surprisingly, Annie discovers that the denizens of this universe measure force in newtons and length in meters. Some things never change, I suppose.

 

During one experiment, Annie observes two objects [r] centimeters apart with qlopz values of [ql1] Œ and [ql2] Œ. Calculate the force between these two objects in terms of Ð (25Ð, ¾Ð, 2.37x10-6 Ð, etc.).  Round your answer to the nearest 0.1Ð N.

 

I worked on this very hard, but gave up when I started to develop a qlopz sweat.

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1 hour ago, Pariah said:

 

Q1 induces a negative charge on the face of the wall closest to it and a positive charge on the opposite side of that wall. Q2 induces a larger positive charge on the face of the wall closest to it, and a correspondingly larger negative charge on the opposite side (i.e., the side closest to Q1). End result: The conducting wall has a negative charge on the side closest to Q1, which exerts an attractive electrostatic force on Q1.  The answer is B.

 

Right...?

 

No.  Q1, outside the box, makes no field inside conductor, explicitly including Q2.  It may exert a force on the box due to the induced charges on the box's outer surface, but unless there's direct mechanical coupling of Q2 to the box that force doesn't affect the free charge inside the cavity in the box.

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Are we Living in the Matrix?

No. Obviously not. It's a daft question. But, buried underneath
this daft question is an extremely interesting one: is it possible to
simulate the known laws of physics on a computer? Remarkably, there is a
mathematical theorem, due to Nielsen and Ninomiya, that says the answer is
no. I'll explain this theorem, the underlying reasons for it, and some
recent work attempting to circumvent it.

 

Colloquium announcement; the talk conflicts directly with my afternoon class, so I can't take it in.

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2 hours ago, Cancer said:

 

No.  Q1, outside the box, makes no field inside conductor, explicitly including Q2.  It may exert a force on the box due to the induced charges on the box's outer surface, but unless there's direct mechanical coupling of Q2 to the box that force doesn't affect the free charge inside the cavity in the box.

 

Oh, that's one the Maxwell Laws, isn't it? Enclosed charge and all that.

Got to look at that more closely.

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On 2/10/2021 at 5:25 PM, Old Man said:

 

Won't someone think of the poor conspiracy theories?!

The CIA does. 

12 minutes ago, Cancer said:

Ahh, but deducting 1 from 3 to get another number is math.

Or the Grnie could just choose 2. 

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On 2/6/2021 at 10:58 PM, Cancer said:

4.  Charges Q1 and Q2 are separated by 0.2 m, and Q1 is inside a conducting box whose nearer wall is halfway between Q1 and Q2.  Q1 = +10 nC; Q2 = -20 nC.  Does Q2 exert a force on Q1, and if so is it an attractive or repulsive force?

 

A) No force

B) Yes, and it's an attractive force

C) Yes, and it's a repulsive force

D) Yes, and while it's not very pretty it is rude to call it "repulsive"

 

EDIT: stupid emoji

D, of course. And you should apologize to Desmond Llewellyn.

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