Question Detail
Question
Evaluate the number of electrons in an X-ray tube that is operated with a voltage of 55 kV and current of 9 mA.
Correct Answer
Option D is the correct answer.
Detailed Explanation
The number of electrons per second (n) is given by the current (I) divided by the charge of one electron (e). I = 9 mA = 9 × 10^-3 A. e = 1.602 × 10^-19 C. n = I/e = (9 × 10^-3) / (1.602 × 10^-19) = 5.618 × 10^16 electrons/s.
Hint
Use the relationship between current, charge, and number of electrons: I = n * e / t. Since current is charge per second, n = I/e.