A minimumenergy of 7.21x10-19 J is required to produce the photoelectric effect in chromium metal. What is the minimum energy required to eject an electron from chromium metal

2.085 x 10^-20 J

Explanation:

minimum energy required to produce photoelectric effect in chromium is given as hf =  7.21 x 10^-19 J

The work function of chromium Ф = 4.37 eV = 7.00151 x 10^-19 J

The minimum energy required to eject an electron from from a chromium metal E = ?

From E = hf - Ф

substituting values, we have

E = (7.21 x 10^-19) - (7.00151 x 10^-19)

E = 2.085 x 10^-20 J

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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