- #1
dannyp
- 3
- 0
I am a third year aerospace engineering student with very little knowledge of eletricity generation. I currently cannot determine the simple derivation of Faraday's first (i think?) experiment of electromagnetic induciton (bar magnet passing through a loop).
Now i understand that the voltage generated is given by:
V = -N dPhi/dt (change in magnetic flux with respect to time * loops) [i understand that a increase in the velocity through the loop increases the voltage generated]
And i know:
phi = integral of (B * dA) [magnetic flux density by the change in area)
B = mu H (magnetic permeability * magnetic field intensity)
With my formulas aside, I would assume the magnetic field intensity drops off as a function of distance from the loop, but i cannot find any information on this (simple bar magnet i using [does the magnet come with a value of B or H?? these are more questions!]).
As a studying engineer i know all actions have a reaction. There must be a force that will appose the motion of the magnet that induces the electricity. How do i find this force. Is it just F = q u x B ? (charge by velocity cross B [what is q? electron charge? bar magnet charge?])
edit: with more loops would a loop closer to the magnet generate more electricity than one further away? how do i add account for this (i have absoloutely no idea!)? [i think i should get the basics down first!]
Any information will be fantastic and greatly appreciated. I thank all in advance.
Daniel
P.S. If you're going to help I suppose you'd like to know what it's for! I'm trying to rig up a linear generator (i guess you'd call it?) for an electric hose reel retractor (yes i know i could use a torsion spring, but wheres the fun)
Now i understand that the voltage generated is given by:
V = -N dPhi/dt (change in magnetic flux with respect to time * loops) [i understand that a increase in the velocity through the loop increases the voltage generated]
And i know:
phi = integral of (B * dA) [magnetic flux density by the change in area)
B = mu H (magnetic permeability * magnetic field intensity)
With my formulas aside, I would assume the magnetic field intensity drops off as a function of distance from the loop, but i cannot find any information on this (simple bar magnet i using [does the magnet come with a value of B or H?? these are more questions!]).
As a studying engineer i know all actions have a reaction. There must be a force that will appose the motion of the magnet that induces the electricity. How do i find this force. Is it just F = q u x B ? (charge by velocity cross B [what is q? electron charge? bar magnet charge?])
edit: with more loops would a loop closer to the magnet generate more electricity than one further away? how do i add account for this (i have absoloutely no idea!)? [i think i should get the basics down first!]
Any information will be fantastic and greatly appreciated. I thank all in advance.
Daniel
P.S. If you're going to help I suppose you'd like to know what it's for! I'm trying to rig up a linear generator (i guess you'd call it?) for an electric hose reel retractor (yes i know i could use a torsion spring, but wheres the fun)
Last edited: