The charge of an electron is 1.6 x 10^-19 C. How many electrons strike the screen of a cathode ray tube each second when the beam current is 16 mA?
Correct answer: C. 1017
- A. 1019
- B. 10-19
- C. 1017
- D. 10-17
Explanation
I = Q / tQ = ne {where n is the number of electrons, e is the charge of an electron}I = ne / t16 x 10-3 = n x 1.6 x 10-19 / 1n = 16 x 10-3 / 16 x 10-20n = 1 x 1017 electrons
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