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ID: 2276381 • Letter: #

Question

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Explanation / Answer

d) at r> 3*R

electric flux = Qin/epsilon

E*4*pi*r^2 = (Q+5*Q)/epsilon

E = 6*Q/(4*pi*epsilon*r^2)

= 6*k*Q/r^2

e)

-Q charge is induces on inner surface

surface charge density = charge/area

= -Q/(4*pi*(2*R)^2)

= -Q/(16*pi*R^2)

f) 6*Q charge is induced opn outer surface

surface charge density = charge/area

= 6*Q/(4*pi*(3*R)^2)

= 6*Q/(36*pi*R^2)


g) V = k*Qin/r

= k*6*Q/(3*R)

=2*k*Q/R