A +15 microC point charge Q1 is at a distance of 20 mm from a + 10 microC charge Q2.
Fin the resultant electric field at:
Ai) the midpoint between the two charges
ii) at point P along the line between Q1 and Q2 which is 25 mm from Q1 and 45 mm from Q2.
bi) Explain why there is a point along the line between the two charges at which the electric field is zero
ii) Calculate the distance from this point to Q1 and to Q2
I know the eleectric field can be calculated using E = (kQ)/r^2 but I am unsure how to calculate this.
The Attempt at a Solution
The answers at the back of the book say the answers are:
ai) 4.5 x 10^8 V/m towards Q2
ii) 2.6 x 10^ V/m away from Q1
bii) 11 mm from Q1, 9 mm from Q2[/B]
But I cant seem to get these answers.