ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: onlyfknhuman on November 08, 2008, 08:23:33 pm

Title: Fakaday's laws.
Post by: onlyfknhuman on November 08, 2008, 08:23:33 pm: Nothing to do with faradays laws but just wanted to bag it.

Anyway...

Does increasing the number coils increase the magnetic field strength in a solenoid:

Heres my theory:

Since increasing the current increases the field strength.

By increasing current your increasing the amount of Positive charged particles inside the solenoid.

So, if your increasing the number of coils, your increasing the number postived charged particles already in the solenoid. Thus increasing the field strength.

So is this legit?
Title: Re: Fakaday's laws.
Post by: mark_alec on November 08, 2008, 11:52:53 pm: Don't know what they want in VCE, but increasing the number of coils in a solenoid (that is being modelled ideally, that is, all the magnetic field is inside and none outside) does not increase the magnetic field strength.

For an ideal solenoid, $B = \frac{\mu_0 iN}{L}$ , where $N$ is the number of turns in a unit length $L$ and $\mu_0 = 4\pi * 10^{-6} Tm/A$ is the Permeability constant.

Suffice to say, the way you increase a magnetic field in a solenoid is to increase the number of coils/unit length, or to increase the current.
Title: Re: Fakaday's laws.
Post by: onlyfknhuman on November 09, 2008, 12:21:00 am: so thsoe factors only increase the magnetic field area, not its density/strength.
Title: Re: Fakaday's laws.
Post by: onlyfknhuman on November 09, 2008, 02:59:50 pm: bump
Title: Re: Fakaday's laws.
Post by: mark_alec on November 09, 2008, 03:44:31 pm: Quote from: onlyfknhuman on November 09, 2008, 12:21:00 am
so thsoe factors only increase the magnetic field area, not its density/strength.
Increasing the coil density or current increases the strength of the magnetic field.
Title: Re: Fakaday's laws.
Post by: onlyfknhuman on November 09, 2008, 04:31:10 pm: okay thanks.