electrostatics

the figure shows the variation of electric field along the x axis

how many position are there of
1. stable equllibrium??
2.unstable equilibrium??
3.total number position of equlibrium state??

2 Answers

106

Asish Mahapatra ·2009-06-23 23:20:29

Stable eqbm when dU/dr = 0 and d²U/dr² < 0
i.e F = E = 0 and dE/dr < 0

Unstable eqbm. when E=0 and dE/dr > 0

EQbm when E=0

So seeing we have 3 stable eqbm and 4 unstable eqbm. Total 7 eqbm posn

thanks

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