we have seen birds perching on high voltage wires. the bird can stand harmlessly on one wire of high potential. why?​

Birds can sit on power lines and not get electric shocks because the electricity is always looking for a way to get to the ground. The birds are not touching the ground or anything in contact with the ground, so the electricity will stay in the power line.

Hope this helps!

and 1and 1

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach