two oppositely charged rings of radius r are separated by a distance 6r. an electron is placed at the centre of the positively charged ring. what min velocity should be given to the electron so that it reaches the centre of the negatively charged ring
two oppositely charged rings of radius r are separated by a distance 6r. an electron is placed at the centre of the positively charged ring. what min velocity should be given to the electron so that it reaches the centre of the negatively charged ring