A 170-km-long high-voltage transmission line 2.00 cm in diameter carries a steady current of 1,010 A. If the conductor is copper with a free charge density of 8.50 1028 electrons per cubic meter, how many years does it take one electron to travel the full length of the cable

The number of years is

Explanation:

From the question we are told that

    The length of the transmission line is  

    The diameter of the transmission line is  

     The current which the transmission line carry is  

      The charge density of the transmission line is  

Now  the cross-sectional  area of the transmission line is mathematically represented  as

Here r is the radius which is mathematically evaluated as

substituting values

Hence

=>      

Now the drift velocity of electron is mathematically evaluated as

Where e is the charge on one electron and the values is  

       So

Now the time taken is  mathematically evaluated as

substituting values

Converting to years

substituting values

it is a negative acceleration