The potential difference applied to an X-ray tube is 5 kV and the current through it is 3.2 mA. The number of electrons striking the target per second is

Options

A. `5 xx 10^16`
B. `2 xx 10^16`
C. `1 xx 10^17`
D. `4 xx 10^15`

Answer

B

Explanation

Number of electrons striking the target of X-ray tube per second is
`n = I/e = (3.2 mA)/(1.6 xx 10^(-19) C) = (3.2 xx 10^(-3 )A)/(1.6 xx 10^(-19) C) = 2 xx 10^16 s^(-1)`