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cryforhelp104
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- TL;DR Summary
- What does a lower case r mean over variables in an equation?
I've attached an example here.
Hi, I attached a photo above. I've re-attached it herejedishrfu said:Can you provide some context like what book you found this notation or in what topic the equation is used?
Unfortunately, the notation is from a power point and has no references.FactChecker said:I am not familiar with that as a common notation. The book or article should define that notation someplace before it is used. It is not uncommon for me to have to scan back through the text looking for a notation definition. If you are lucky, there might be a section where all notation is defined.
Dude... it's one of Maxwell's equations. This is from a publicly available slide in my modern physics lecture. The E script stands for the electric field. The powerpoint doesn't have references. The link to the publicly available powerpoint is here. It's on slide 25.jedishrfu said:When we ask for context, we mean some reference?
What does the script E stand for?
Could this be some kind of directional derivative along a position vector R or does R represent the real number system?
There is no way to help you here without some context.
Your reluctance implies this is some sort of privileged information from either a company or government source and you can’t divulge that if so then there’s nothing more to do here.
I’ve searched several places and have come up with nothing of note So we are at a dead end without context.
Lastly, please don’t give out any corporate confidential or classified information here.
My suggestion is to go ask the PowerPoint presenter what it means.
It would have been good to tell us this, dude.cryforhelp104 said:Dude... it's one of Maxwell's equations.
The 'r' characters in the image are an artifact of copying from the PowerPoint deck. They are supposed to be arrows that signify vectors. The characters aren't present in the original deck.cryforhelp104 said:TL;DR Summary: What does a lower case r mean over variables in an equation?
View attachment 338492
I've attached an example here.
Dude, lose the 'tude!cryforhelp104 said:Dude...
In mathematics, a lower case r over a variable in an equation usually denotes a vector quantity. This means that the variable represents both magnitude and direction in a specific coordinate system.
Distinguishing vector quantities with a lower case r helps in understanding the physical meaning of the variable in the context of the equation. It also helps in performing vector operations correctly.
Yes, variables with lower case r over them can be used in scalar equations. In scalar equations, the vector quantity represented by the variable is usually simplified to its magnitude, which is a scalar value.
Yes, besides using a lower case r over variables, vector quantities can also be denoted using boldface letters or arrows above the variable. These notations all convey the same meaning of representing a vector quantity.
Vector quantities with lower case r follow specific rules in mathematical operations such as addition, subtraction, and multiplication. These operations are typically performed component-wise to account for both magnitude and direction of the vectors.