Proctoring a physics 1 exam and seeing students do both these and curling their fingers around (thumb in direction of current, curl fingers around direction of magnetic field) was always very humerous to see.
this post was submitted on 21 Dec 2023
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I was totally unable to understand that. As simple as it is. Got my physics minor basically getting every single rhr question wrong. Don't know how I managed it
I hated the hand thing. Instead I remembered it working like the polarity of the "tan" function since that was easy for me to picture.
a = 1 finger
b = 1 finger
a x b = 1 x 1 = 1 thumb
checks out 🤓
Also applicable in a modified way in biology, useful for keying snails
That's kind of rude, then they'll have to get their house repainted
Tbh I never understood this rule very well and I did my undergrad in physics. My teacher or prof would teach this but I'd forget it almost instantly.
To visualize a cross product, I just remember that x cross y = z, then remember how the axes are oriented.
