Question

Sensitive instruments can detect the passage of as few as 60 electrons/s. To what current does this correspond?

Answer 1

`9.6\cdot 10^(-18) A`

Step-by-step explanation:

Current is defined as

`I=(Q)/(t)`

where

Q is the charge passing through a given point

t is the time interval

The SI unit of the current is the Ampere (A), where

`1A = 1C/s`

which means 1 Ampere is 1 Coulomb per second.

The charge of 1 electron is (in magnitude)

`e=1.6\cdot 10^(-19)C`

So, the charge of 60 electrons is

`Q=Ne=(60)(1.6\cdot 10^(-19))=9.6\cdot 10^(-18) C`

Therefore, if there are 60 electrons passing per second, the current is

`I=(9.6\cdot 10^(-18) C)/(1 s)=9.6\cdot 10^(-18) A`