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Unformatted text preview: Probiem 2 [25]. A nonconducting sphere has radius R and volume charge density pis
centered at the origin. a) {5] What is the E—ﬁeld outside the. Sphere? Shoueur work. 7)
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Eb E Gina") 19:3 b} [ID] A particle with charge. Q and mass m. is released from a point (I meters away from
the surface of the sphere. Find the article’s s eed when it reaches a position 2d from the surface of the sghere. an $33 +I>E;, =KE;*PEF I
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Rsrd 3' R+ 2‘1 c} 1'10] A uniform line charge with total charge Q _ _ d
is oriemed radially with respect to the sphere with
its ends :1! R and R+a'. What is the force on the line charge? I Hint: lzdrz—l
r r 3. I'Scl'orc the dielectric is InscrrctL we have E93 0 Qd
d C Q=cv,c= After the dielectric is inserted, the capacitor can be considered as two half—plales. one without the diclccuic, the other with
lhc dielectric. Each halfplate forms a new capacitor‘ and die Iwo capacitors are in parallel because they have the same
potential. Thu: half—plate. wilhoul the dielcciric has capacitance {:9 A / 2 so A C]_ _ I
('1 2d while lhc halfplalc with the diclctric (x = 7] has capacitance (Ken) AJ’Z 69A
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electric field between them. An electron is released from the negative plate at the same time that a proton is released from the positive plate. Neglect the force of the particles on each other and ﬁnd their distance from the positive plate when they
pass each other. Use symbols for the various charges, masses, etc. ASKSJN \Jﬁlﬁ/M LLpCVﬁg [AM (QNGMh+
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This note was uploaded on 03/08/2011 for the course PHYS 8B taught by Professor Catherinebordel during the Spring '10 term at Berkeley.
 Spring '10
 CatherineBordel
 Physics

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