Question

The electron beam inside a television picture tube is 0.40 mm in diameter and carries a current of 50 micro-A This electron beam impinges on the inside of the picture tube screen.

a) How many electrons strike the screen each second?

Answer 1

To find the number of electrons that strike the screen each second, calculate the charge passing through the screen and then convert it to the number of electrons. The number of electrons striking the screen each second is 3.12 × 10^13 electrons.

Step-by-step explanation:

To find the number of electrons that strike the screen each second, we need to first calculate the charge passing through the screen in one second. Using the equation Q = I * t, where Q is the charge in Coulombs, I is the current in Amperes, and t is the time in seconds, we have Q = (50 * 10^-6 A) * 1 s = 50 * 10^-6 C.

Next, we need to calculate the number of electrons in this given charge. We know that 1 Coulomb is equal to 6.242 × 10^18 electrons, so the number of electrons striking the screen each second would be (50 * 10^-6 C) * (6.242 × 10^18 electrons/C) = 3.12 × 10^13 electrons.