Question

an electric field has a strength of 10.0 N/C at a distance of 1.00m from an unknown charge. At what distance from the charge does the electric field strength equal 2.50 N/C?

Answer 1

r = 1.999m

Step-by-step explanation:

E = kq/r²

10 = 9*10^9*q/1²

q = 10/9*10^9

q = 1.11*10^-9

then at what distance

r² = kq/E

r² = 9*10^9*1.11*10^-9/2.5

r² = 9.99/2.5

r² = 3.996

r = √3.996

r = 1.999m