Question

Pls explain what happens here. and no spam plss​

Answer 1

Answer:

hii freind

though i have recently given my 12 boards so i can understand it

here the distance between twoo charges is r which is more greater than the distance between another charge whichs distance is a.. if u subtract a square of r with square of a it will not readily effect the value of r. just like if u subtract 5 with 0.001 u got the ans 4.999 which is readily aceeptable as 5. so in that way here suppose 5 is r and a is 0.001 it will readily effect because it is of square of it.. so we neglect it it doesn't effect the ans..

hope u can understand it... thnks for any other info. comment it i will reply ..if u like the ans mark it brainellist.. thnks