Finding the electric potential energy

AI Thread Summary
To find the electric potential at the origin due to two charges, the first charge is -2.580 μC at (2.575 m, 4.742 m) and the second charge is 1.440 μC at (-2.730 m, 0). The distance from the origin to the first charge, calculated using the Pythagorean theorem, is approximately 5.396 m. The potential is calculated using the formula V = (k*q1)/r1 + (k*q2)/r2, where k is the Coulomb's constant. The initial calculation yielded -9040 V, which was identified as incorrect, prompting a re-evaluation of the signs and contributions of the charges.
sameasabuv
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A charge of -2.580 mu C is located at (2.575 m, 4.742 m), and a charge of 1.440 mu C is located at (-2.730 m, 0). Find the electric potential at the origin.

q_1= -2.580*10^-6 C
q_2= 1.440*10^-6 C
k = 8.99*10^9 N*m/C^2
r_2= -2.730 m

V= (k*q_1)/r_1 + (k*q_2)/r_2


So first i found r_1 by using the Pythagorean theorem r_1= √(2.575^2 +4.742^2)= 5.396 m
Then i plugged all the information into the above equation (converting the mu C to C) i came up with the answer -9040 V but it's the wrong answer and i can't figure out what i did wrong.
 
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Check your math. Using your numbers I got a potential of about -4300 V due to the negative charge. The positive charge would only make that number bigger, I can't get your number?
 
sameasabuv said:
A charge of -2.580 mu C is located at (2.575 m, 4.742 m), and a charge of 1.440 mu C is located at (-2.730 m, 0). Find the electric potential at the origin.

q_1= -2.580*10^-6 C
q_2= 1.440*10^-6 C
k = 8.99*10^9 N*m/C^2
r_2= -2.730 m

V= (k*q_1)/r_1 + (k*q_2)/r_2

So first i found r_1 by using the Pythagorean theorem r_1= √(2.575^2 +4.742^2)= 5.396 m
Then i plugged all the information into the above equation (converting the mu C to C) i came up with the answer -9040 V but it's the wrong answer and i can't figure out what i did wrong.

Homework Statement



Homework Equations



The Attempt at a Solution

Hello sameasabuv. Welcome to PF!

Don't forget, q1 and q2 have opposite sign.
 
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