How Do You Calculate the Electrostatic Force Between Two Charged Particles?

[tag16]

Homework Statement

Particle A with a charge of 45 micro Coulombs is located on the x-axis at a point -11 cm from the origin. Particle B with a charge of 41 micro Coulombs is located on the y-axis at a point +68 cm from the origin. What is the magnitude of the electrostatic force that Particle A exerts on Particle B? (Answer in Newtons.)

Homework Equations

Coulomb's Law: Fe=ke(q1q2/r^2)

The Attempt at a Solution

(8.99x10^9)((45x10^6)(41x10^6))/11^2

(8.99x10^9)((41x10^6)(41x10^6))/2(68^2)

Not sure what to do next or if this is even right so far. I think I have to do something w/ the x and y components and find the degree of the angle, which I'm not sure how to do.

 

[rl.bhat]

First of all convert distances from cm to meter. Then find the distance r between A and B.
Now using the relevant equation find the force on B by A.

 

[tag16]

so would it be (8.99x10^9)((4.5x10^-5)(4.1x10^-5))/(.79)^2 ?

 

[tag16]

what do you have to do differently when one charge is on the x-axis and the other is on the y-axis as appose to them both being on the x-axis and you just add them together?

 

[rl.bhat]

so would it be (8.99x10^9)((4.5x10^-5)(4.1x10^-5))/(.79)^2 ?

The distance between A and B is sqrt(OA^2 + OB^2)
O.79 m is the distance between A and B if they are on the x axis.

 

[tag16]

so what if one of the charges is on the y axis?

 

[rl.bhat]

so what if one of the charges is on the y axis?

Then the distance between A and B is sqrt(OA^2 + OB^2)