Mostrar código-fonte de Debye shield /spherical conductor

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*CONTEXTO : Segundo ciclo universitário
*AREA: Física
*DISCIPLINA: Física e Tecnologia dos Plasmas
*ANO: 4
*LINGUA: en
*AUTOR: Vasco Guerra
*MATERIA PRINCIPAL: Debye shielding and fundamental efects
*DESCRICAO: Debye shield /spherical conductor
*DIFICULDADE: *
*TEMPO MEDIO DE RESOLUCAO: 300 [s]
*TEMPO MAXIMO DE RESOLUCAO: 600 [s]
*PALAVRAS CHAVE: 
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(F. F. Chen \(\sim\)  1.10) A spherical conductor of radius \(R\) is immersed in a plasma and charged to a potential \(\phi_0\).
The electrons remain Maxwellian and move to form a Debye shield, but the ions are stationary during the time frame
of the experiment. Assuming \(e\phi_0\ll k T_e\):

(a) derive an expression for the potential as a function of \(r\);

(b) calculate the charge in the sphere;

(c) calculate the sphere capacity for \(R=10\) cm, \(T_e=1\) keV and \(n_0=10^{14}\) and \(10^6\) cm\(^{-3}\), and show that for 
high electron densities the plasma behaves as a dielectric.