Question

In: Physics

Over and over I'm getting into the same trouble, so I'd like to ask for some...

Over and over I'm getting into the same trouble, so I'd like to ask for some help.

  1. I need to solve some basic electrodynamics problem, involving magnetic fields, moving charges or currents.
  2. But I forgot all this rules about "where the magnetic field should go if the current flows up". I vaguely remember that it about hands or fingers or books or guns, and magnetic field should go somewhere along something, while current should flow along something else... But it doesn't help, because I don't remember the details.
  3. I do find some very nice rule and use it. And I think "that one I will never forget".
  4. ...time passes...
  5. Go to step 1.

The problem is that you have to remember one choice from a dichotomy: "this way or that way". And all the mnemonics I know have the same problem -- I got to remember "left hand or right hand", "this finger or that finger", "inside the book or outside of the book".

Maybe someone knows some mnemonics, that do not have such problem?

Solutions

Expert Solution

if the electric field is a vector with an arrow, then the magnetic field is fundamentally not a vector: instead, it is an antisymmetric tensor with two indices, determining an "oriented two-plane".

The latter carries the same information (3 different components) as a vector, and there is a convention given by the right-hand rule to switch from one to the other. A derived and related rule also determines the magnetic field of a solenouid and other things.

Clearly, the convention to switch from the antisymmetric tensors to vectors could have been the other way around, too. So one has to remember something to know the convention; one can derive many things but not conventions. I agree that remembering the right hand operations is simple, especially because the word "right" also means "correct" and because the right-wing political opinions are the right ones while the left-wing political opinions are those that are left over.


Related Solutions

I'd like to have the same of this sample of the family nursing care plan but...
I'd like to have the same of this sample of the family nursing care plan but as a risk of fall nursing diagnosis from the water leaking Sample Family Nursing Care Plan (FNCP) Case: This is a case of S. Family. S. Family is composed of 5 children and both parents were alive. Upon observation the family practices improper hygiene in eating and waste disposal. The 5 children have 2 to 3 years of age gaps, having the youngest child...
Intro to Python I'm getting trouble obtaining the solution for the following questions: "How many babies...
Intro to Python I'm getting trouble obtaining the solution for the following questions: "How many babies were born with names starting with that least-common letter?" For the file used it is "U" "How many babies were born with names starting with that-common letter"? For the file used it is "A" "How many people have that name?" (This follows the question "By default, the Social Security Administration's data separates out names by gender. For example, Jamie is listed separately for girls...
I'm have trouble change JRadioButton and do not want to select all at the same time...
I'm have trouble change JRadioButton and do not want to select all at the same time just one at a time. if one of them is unselected, then set the font as plain. Set font size as 20. run the program and change the font and you see what I'm talking about also this there anyway to shorten my code import java.awt.BorderLayout; import java.awt.Color; import java.awt.Desktop; import java.awt.Font; import java.awt.event.*; import java.net.URL; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.FileReader; import java.io.FileWriter;...
So though I was on question 3 as well, I'd like to place in the discussion...
So though I was on question 3 as well, I'd like to place in the discussion the patient portal access along with the bar-code scanning and clinical alerts like Elsie mentioned in her PowerPoint. The patient portal would be part of my top three only because we are in a business that it's main focus is on patient care and customer service, and of course the bottom line really is to make money. Here are some benefits to having the...
​​​​​​This is an assignment that I'm having trouble figuring out in python: Modify Node class so...
​​​​​​This is an assignment that I'm having trouble figuring out in python: Modify Node class so it has a field called frequency and initialize it as one. Add a search function. If a number is in the list, return its frequency. Modify Insert function. Remove push, append, and insertAfter as one function called insert(self, data). If you insert a data that is already in the list, simply increase this node’s frequency. If the number is not in the list, add...
For this discussion, I'd like you to discuss some of the pros and cons of full...
For this discussion, I'd like you to discuss some of the pros and cons of full absorption costing (GAAP) versus variable costing (Internal). Why do you think GAAP requires full absorption costing? Income tax accounting also requires full absorption costing. Why do you think that would be? This subject is certainly discussed in the book, so please don't just rehash what the book has told you. Instead, please interpret the pros and cons identified in the book as well as...
Hey! I'm having trouble answering this for my assignment. Thank you so much in advance. 1)...
Hey! I'm having trouble answering this for my assignment. Thank you so much in advance. 1) Which type of vessels, arteries or veins, has more muscle fibers? What is the functional significance of this? 2a) In general, we have no conscious control over smooth muscle or cardiac muscle function, whereas we can consciously control to some extent all skeletal muscles. Can you consciously control your breathing? What does this tell you about the muscle type of the diaphragm? 2b) What...
I'd like some suggestions for good reading materials on the Keldysh formalism in a condensed matter...
I'd like some suggestions for good reading materials on the Keldysh formalism in a condensed matter context. I'm familiar with the imaginary time, coherent state, and path integral formalisms, but lately I've been seeing Keldysh more and more in papers. My understanding is that it is superior to the imaginary time formalism at least in that one can evaluate non-equilibrium expectations.
Hi, I'm having some trouble with this question, especially part B. Stocks offer an expected rate...
Hi, I'm having some trouble with this question, especially part B. Stocks offer an expected rate of return of 18%, with a standard deviation of 22%. Gold offers an expected return of 10% with a standard deviation of 30%. a) In light of the apparent inferiority of gold with respect to average return and volatility, would anyone hold gold in his portfolio? (4 points) b) Assume that the correlation between Stocks and Gold is -0.5. Find the weights wS and...
Hi! I have some questions I'd like to discuss regarding an experiment with the pendulum I...
Hi! I have some questions I'd like to discuss regarding an experiment with the pendulum I will have a laboratory class in which I will have to measure the period of oscillation of the swinging pendulum using an electronic stopwatch. what method could I use to obtain the period of a physical pendulum using a stopwatch, taking care to minimise any uncertainties? Can you help me to go through this questions? Should you start the stopwatch at the same time...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT