In the following four cases, charged particles are at equal distances from the origin. Arranged them in the descending order of magnitude of the net electric field at the origin.

Options

A. 1, 2, 3, 4
B. 2, 1, 3, 4
C. 1, 3, 2, 4
D. 4, 3, 2, 1

Answer

C

Explanation

If electric due to charge `abs(q)` at origin is E then field due to charges `abs(2q), abs(3q), abs(4q) " and "abs(5q)` are respectively 2E, 3E, 4E and 5E respectively.

So, the electric field, `E_(1)=sqrt((5E)^(2)+(5E)^(2))=5sqrt(2)E`
`" "E_(2)=sqrt((3E)^(2)+(3E)^(2))=3sqrt(2)E`
`" "E_(3)=4E+2E=6E`
`" "E_(4)=3E+E=4E`
Hence, descending order of magnitude of net electric field is 1, 3, 2, 4.