Question

The current in a Crookes tube is $10nA$. How many electrons strike the face of the glass tube each second?

Short answer

Number of electrons striking the surface are$6.25\times {10}^{10}$.

Step-by-step solution

Step 1. Given information

Current in a Crookes tube is given as $i=10nA$. We have been asked how many electrons will strike the surface of the glass tube each second.

Step 2. Simplify

Current is defined as charge per time

$i=\frac{n\times e}{t}$

where n =number of electrons ,e=charge of each electronlocalid="1649752407663" $\left(=1.6\times {10}^{-19}C\right)$and t is time$\left(=1sec\right)$

solving

$n=\frac{i\times t}{e}=\frac{10\times {10}^{-9}\times 1}{1.6\times {10}^{-19}}=6.25\times {10}^{10}$