A pure Silicon crystal has 700,000 free electrons (actual number of electrons; not the concentration). How many holes does it have

700,000 holes

Explanation:

When heat energy occurs to produce free electrons, the number of free electrons produced is directly proportional and equal to the number of holes it produces at that time.

Hence, if silicon crystal (pure) has 700,000 free electrons, then the number of holes it have is also 700,000.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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