Suppose that 300 keV X-ray photons are aimed at a zinc cube (Zinc, Z = 30). According to the chart below, what effect will predominate when the X-rays hit the metal? a) Photoelectric Effect 3
b) Compton Effect 3
c) Pair Production

the answer is option A = photoelectric effect

Explanation:

If the threshold frequency of a metal is lower than the energy of X-rays, then photoelectric effect will happen.

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more

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