!MORE TO KNOW!
The average drift speed of an electron in a conductor is 1mm/sec. Isn't it very small!
*BUT THEN WHY* a bulb starts glowing as soon as we turn on the switch??
Consider this GIF
Each stack can be assumed to an electron. As soon as the potential difference is applied, first electron starts to push each subsequent electron and so does the second, third, fourth and every following electron. The last electron when experiences the push moves and the current gets generated. It's not necessary for the First electron to reach the Bulb to make it glow.
*BUT WHY?*
A Bulb would of cource not require an electron to glow, what it needs is energy. And for energy transfer, it's not necessary for First electron of the Wire to reach the bulb. The last electron when moves, provides space of every other electron to move which generates energy and bulb glows.
And this happens far quicker than displacing an electron from starting of the wire to the end of the wire.









