Having trouble finding the potential between two positive point charges.

AI Thread Summary
To find the electric potential between two positive point charges, the potential is calculated by summing the individual potentials from each charge. The user correctly identifies the distances and uses the formula V = k(q1/r1 + q2/r2) with appropriate unit conversions. However, there is a discrepancy in the final potential calculation, as the expected answer is 2.34 * 10^6 V, while the user arrives at 9.10 * 10^5 V. The forum participants emphasize the need for complete working to identify the error in the calculations. The discussion highlights the importance of careful unit management and formula application in electrostatics problems.
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Homework Statement





How to find the potential between two positive point charges?

I don't know where I'm going wrong.

==I am adding V_1 and V_2. converted mC to C, cm to m, correct value of k.

V1= kq1 / r1
v2= kq2/ r2.


==I am adding both of these, but I'm not getting the correct answer.

===Problem:

A point charge of q1 = 2.37 µC is 44 cm from a charge of q2 =26.4 µC. Where is the electric field zero? What is the value of the potential there?
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electric field is zero at 0.101m (correct answer).

I have r1= .101m and r2= .44m - .101= .34m.

I'm using the correct value of k.

== The answer is given as 2.34 * 10^6 V.


Can you help me find out where I'm doing wrong?
 
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We cannot tell where you are going wrong if you do not post all your working.
 
haruspex said:
We cannot tell where you are going wrong if you do not post all your working.


Edit: The potential at the point is equal to the sum of the two potentials of the two point charges.

V= kq_1 / r_1 + kq_2 /r_2

V= (9*10^9 Nm^2/C^2)* (2.37 * 10^-6 C)/ .101m + (9*10^9 Nm^2/C^2)*(26.4*10^-6 C) / .34m = 9.10*10^5 V.

The correct answer is 2.34 *10^6 V.

I don't know what I'm doing wrong.
 
I agree with your answer (almost: 9.11e5).
 
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