Problem 1

Contributed by Siddharth Tiwary (Indian Institute of Technology Bombay).

Two metal balls, both of mass M and radius R , are connected with a rigid dielectric weightless rod of length L , assume that L\gg R . The system is placed into a uniform external electric field of strength E ; neglect gravity and friction forces. Find the period of small oscillations of this system around its stable equilibrium state.

Translation into Chinese

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