Solve Electric Field Problem: Find q1 and q2

AI Thread Summary
The discussion focuses on solving for two point charges, q1 and q2, based on the behavior of a third charge, -1.75 mC, placed between them. The initial acceleration of the charge is noted as 324 m/s² upward, which is crucial for calculations. Participants point out discrepancies in calculations, particularly regarding the mass used, the units of charge, and the angle applied in the solution. One participant questions the use of sine versus cosine in their calculations, suggesting that the angle might have been miscalculated. Clarifications and corrections are sought to ensure accurate results in determining the values of q1 and q2.
NickPA
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Two point charges q1 and q2 are held in place 4.50 cm apart. Another point charge -1.75 mC of mass 4.50 g is initially located 3.00 cm from each of these charges (the figure ) and released from rest. You observe that the initial acceleration of -1.75 mC is 324 m/s^2 upward, parallel to the line connecting the two point charges

Find q1 and q2 ?

I attached a pic of my work.
 

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Hello NickPA. Welcome to PF!

Your method of solution looks good. But I don't agree with your value of the angle ø. Also, in the problem statement the mass is given as 4.50 g whereas in your calculation you use 5.00 g. In the statement of the problem, Q is given in mC whereas in your calculation you use μC.
 
it is supposed to be 5 g. Bad copy and paste sorry. That seems to be the difference between my answer and the right answer. They (the book authors) are using cos, while i used sin, but should it not work?
 
I don't see how you got 41.3 degrees for the angle ##\phi## shown in your figure. Can you show your work here?
 

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