I've done this problem at least 85 times what am I doing wrong?

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The discussion revolves around a physics problem involving two charged plastic chips with a mass of 4.5x10^-5 kg and a distance of 1.5 mm between them. The user calculated the weight of one chip as 0.0441 N but mistakenly used the mass as 0.0045 kg instead of the correct 0.000045 kg. This error led to incorrect calculations for the electrostatic charge needed to balance the weight. The community member pointed out the mistake, emphasizing the importance of accuracy in unit conversions. The user expressed frustration after multiple attempts to solve the problem, highlighting the challenge of the assignment.
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Homework Statement


"Two tiny chips of plastic masses 4.5x10^-5 are separated by a distance of 1.5 mm. Suppose that they carry equal and opposite electrostatic charges +/-q. What must the magnitude of the charge be if the electric attraction between them is equal to the weight of one chip?"

Homework Equations


Fe=k*[(qxq)/d^2]
weight= mass (in kg) x 9.8 m/s^2
q=charge
d=distance
k=Coloumb's constant, 8.99x10^9


The Attempt at a Solution


1. First I have calculated the weight of one mass: .0045kg x 9.8 = .0441 N
2. then I set that equal to Coloumb's eq to try to solve for q. I divided k to the left so .0441 / 8.99x10^9 = 4.9054x10^-12.
3. I multiplied 4.9054x10^-12 by d^2 (or .0015^2) and got 1.1x10^-17
4. At this point I have q^2=1.1x10^-17 so I do a square root and get 3.322x10^-9. I have tried to tweek my answer so many times but to no more avail. I have spent almost an hour on this problem (pathetic, I know) but this problem set is due tomorrow and smartwork is being uncooperative. I would really appreciate any help!
 
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welcome to pf!

hi vitaebellaa! welcome to pf! :smile:
vitaebellaa said:
"Two tiny chips of plastic masses 4.5x10^-5
…
1. First I have calculated the weight of one mass: .0045kg x 9.8 = .0441 N

shouldn't that be 0.000045 ? :redface:
 
WOW! 85 times? ... i have to say .. you got patience
 

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