Correct! Current is a scalar and not a vector, so we don't worry about the direction of the velocity here because it won't affect the answer. Imo the equation would be better written with speed instead of velocity
Might be worth adding that at 2:23 the n = 8.5 x 10^28 electrons/m³ comes from the density, atomic weight and valency of copper. One cubic metre of copper weighs 8.96 x10^6 grams which divided by the atomic weight 63.55 gives 140,991.35 moles of copper. Multiply that by Avogadro's number 6.022 x10^23 and you get 8.49 x10^28 valence electrons per m³ from the 4s(1) shell, which are the conduction electrons in the metal.
Hi and thank you for your videos. Any chance you could explain the concept of Drift Velocity for AC current? Am I right to say that velocity is zero since electrons move back and forth of the same distance? Thank you
The GOAT
Amazing. Concise and helpful all im missing are the HL topics now
THE GOAT🔥
In the last question, wouldn't the velocity be negative, since charge of electron is -1.602*10^-19. so if charge is negative, v would be too
Correct! Current is a scalar and not a vector, so we don't worry about the direction of the velocity here because it won't affect the answer. Imo the equation would be better written with speed instead of velocity
Might be worth adding that at 2:23 the n = 8.5 x 10^28 electrons/m³ comes from the density, atomic weight and valency of copper. One cubic metre of copper weighs 8.96 x10^6 grams which divided by the atomic weight 63.55 gives 140,991.35 moles of copper. Multiply that by Avogadro's number 6.022 x10^23 and you get 8.49 x10^28 valence electrons per m³ from the 4s(1) shell, which are the conduction electrons in the metal.
0:10 sir it`s not point it`s area
Hi and thank you for your videos.
Any chance you could explain the concept of Drift Velocity for AC current? Am I right to say that velocity is zero since electrons move back and forth of the same distance? Thank you
The electrons are moving back and forward with a variable "drift" velocity which varies from positive to negative in a sinusoidal manner..
very useful, many thanks!