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प्रश्न
An isolated metal sphere is heated to a high temperature. Will it become positively charged due to thermionic emission?
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उत्तर
Yes, it will become positively charged due to thermionic emission. When the metal sphere is heated, average kinetic energy of the electrons will increases, due to which, the free electrons of the metal sphere will be able to escape. As a result, they will leave a positive charge on the isolated metal sphere.
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