Question

The potential difference applied to an X-ray tube is $5kV$ and the current through it is $3.2mA$. The number of electrons striking the target per second is (Take $e=1.6\times {10}^{-19}C)$.

• A. $1.6\times {10}^6$
• B. $2\times {10}^{-6}$
• C. $4\times {10}^{16}$
• D. $2\times {10}^{16}$

Answer 1

The correct option is D $2\times {10}^{16}$

Current $i=\frac{ne}{t}$
$\Rightarrow \frac{n}{t}=\frac{i}{e}=\frac{3.2\times {10}^{-3}}{1.6\times {10}^{-19}}=2\times {10}^{16}/s$.