Calculating Force on a 1uC Charge

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Homework Statement


Find Force at 1uC charge
https://i.gyazo.com/12891ce5b3adc422acc64daa6e8d3f25.png
Right triangle with a right angle at the top vertex labelled 1uC. The side from the top vertex to the bottom-left vertex is 10 cm, labelled 2x10^-8C there. The side from the top vertex to the right vertex is 5 cm, labelled -10^-8 C there.


Homework Equations


Equation: magnitude of F equals k_e times the absolute value of q1 q2, divided by r squared.

The Attempt at a Solution


Assume 1uC charge is at point P 2*10^-8C is at A and 10^-8C is at B
FP = FPA + FPB

FPA = K*2*0.01*1/100
= 0.0002*K
= 2k* 10 ^-4

FPA = K*0.01*1/25
= 0.00004*K
= 4K x 10^-4

Now adding them using vector addition,
sqrt((4K*10^-4)^2 + (2K*10^-4)^2 + 0) --(cos(90) will be 0)
sqrt((20K*10^-16)
 
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  • Screenshot of the Physics Forums Create Thread page titled Find force on charge, with the 'Similar discussions' box and an empty problem statement field reading 'Find Force at 1u' and 'c'.
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Your handling of the powers of ten looks off (or you are using nonstandard units for force).
What's 10-6x10-8?
Later, what's (4k10-4)2?