(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Bringing a strong magnet close to an operating incandescent light bulb has the effect of breaking the filament. Breakage might be expected when the extra force on the filament becomes comparable with gravity. Estimate the field strength likely to cause problems with a 60W bulb, in which the diameter of the tungsten filament is 0.1mm. (Density of tungsten = [tex] 19.3 x 10^3 kg.m^-^3 [/tex].)

2. Relevant equations

[tex] Density = \frac{mass}{volume} [/tex]

[tex] VI = P [/tex]

[tex] \int B\dot dl = \mu_0 I_{encl} [/tex] <--not sure on the relevance

[tex] F = q[E + v \times B] [/tex] I think this should be equal to [tex] F = mg [/tex]

3. The attempt at a solution

I can work out individual components, such as the current flowing through the wire (assuming that the source is 240V), but I can't seem to be able to make a connection between everything to get a useful formula.

Anyone got any ideas what would be the best thing to do first in this exercise?

TFM

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# Homework Help: Breaking Filaments using magnets.

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