Is this easy charge problem correct?

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SUMMARY

The discussion focuses on calculating the forces acting on three point charges in a two-dimensional plane. The charges are -1.0 µC at the origin, 2.6 µC at (0, 0.1 m), and 13 µC at (0.2 m, 0). The calculated y-force on the 2.6 µC charge is +0.2 N after considering the attractive force from the -1.0 µC charge and the repulsive force from the 13 µC charge. The participant also highlights the importance of using tangent functions to avoid rounding errors in angle calculations.

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Homework Statement


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A charge of -1.0 µC is located at the origin, a second charge of 2.6 µC is located at x = 0, y = 0.1 m, and a third charge of 13 µC is located at x = 0.2 m, y = 0. Find the forces that act on each of the three charges.
I need to find the y forces on the charge 2.6 µC. I have one last try.

Homework Equations


-----------------------------------------
F=k*((q1)(q2)/r2)
K = 9E9 Nm2/c2
q1= charge 1 in columbs
q2 = charge 2 in columbs
r = distance between the two charges (in meters)

a2 + b2 = c2
sin(xº)=O/H

#1E#2 = #1*10^#2

The Attempt at a Solution


-----------------------------------------
F1 = 9E9 * ((2.6µC)*( -1.0µC))/.12
F1 = -2.34 N
*It's negative because its being pulled down due to attraction

F2 = 9E9 * ((2.6µC)*( 13.0µC))/.2242
F2 = 5.6 N
**.1m2 +.2m2 =.05 , .05.5 = .224m **
**.1m and hyptonuse angle: sin-1(.2m/.224) = 63.23º **
** Other angle is 26.76º (90º-63.23º)**
sin(xº)=O/H --> H*sin(xº)=O
5.6 N sin (26.76º) = +2.54 N

+2.54 N - 2.34 N = +.2 N
Is this the correct answer? +.2N
------------------------------------
I tried using 5.6cos(26.56º) = 5.009N (Hcos(xº) = A) for the x forces and it told me I was wrong. I plugged in 5 N & -5 N :|
 
Last edited:
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The physics looks good. I didn't check the calculator work, except for the angle - and I got 26.56 degrees instead of your 26.76 degrees. Better check that again. Use tan instead of sin so you don't get any rounding error due to the hypotenuse calc.
 

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