Which of the follwing characteristies of electrons determines the current in a conductor?

Options

A. Drift velocity alone
B. Thermal velocity alone
C. Both drift velocity and thermal velocity
D. Neither drift nor thermal velocity.

Answer

A

Explanation

The current in a conductor is given by
`I = n eAV_(d)`
where n= charge density of electrons
e= charge on an electron
A= area of cross section of the conductor
`V_(d)`= drift velocity of electrons
From the above expression we can conclude that current I is a function of drift velocity of electrons i.e.,
`I= f(V_(d))`
Current in the conductor is due to drift velocity of electrons and has nothing to do with their thermal velocity. Also, the thermal velocity of electrons is random and do not contribute to current. Thus option (a) is correct