I know everything to do on this problem except one thing

[flamebane]

Homework Statement

Two charged particles A (qA = 2.86 𝜇C) and B (qB = 1.47 𝜇C) are fixed in place along the x-axis at 𝑥 = ±3.38 cm, respectively. If a third charged particle C (qC = 3.92 𝜇C and mass mC = 10.21 mg) is released from rest on the y-axis at y = 2.57 cm, what will the speed of particle C be when it reaches 𝑦 = 4.43 cm? Answer in m/s

Relevant Equations

principle of conservation of energy
KE

Even though I have all the formulas needed to do this problem, I cant figure out how to get rA, rB and rA' aswell as rB'

 

[jbriggs444]

Even though I have all the formulas needed to do this problem, I cant figure out how to get rA, rB and rA' aswell as rB'

You could start by showing us the formulas that you plan to use. But perhaps we need to back up a step. Can you explain your strategy? What formulas are justified by the physical situation? Please provide that justification.

Then you would be in a position to explain what $r_A$, $r_B$, $r_A'$ and $r_B'$ are.

[And we might be in a position to recommend the Pythagorean theorem]

 

[flamebane]

You could start by showing us the formulas that you plan to use. But perhaps we need to back up a step. Can you explain your strategy? What formulas are justified by the physical situation? Please provide that justification.

My strategy is to first find all the potential and kinetic energy of particles A and B, then C. then using the principle of conservation of energy to find V.

 

[flamebane]

My strategy is to first find all the potential and kinetic energy of particles A and B, then C. then using the principle of conservation of energy to find V.

I know what the r's mean I just dont really know how I'm ment to get it, would I use the distance formula?

 

[kuruman]

My strategy is to first find all the potential and kinetic energy of particles A and B, then C. then using the principle of conservation of energy to find V.

Then start by writing some equations for the potential and kinetic energies. If there are quantities that you don't know how to express, point them out. A diagram should help.

 

[jbriggs444]

I know what the r's mean I just dont really know how I'm ment to get it, would I use the distance formula?

You may know what the r's mean. But we do not. Because you have not told us.

I could make a good guess that $r_A$ is the distance from <somewhere> to <somewhere else>. Yes, if so, then the formula for calculating the distance from <somewhere> to <somewhere else> will be important.