Debye shield /spherical conductor
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Metadata
- 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:
(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.