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Darth Frodo
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Homework Statement
2 point charges are situated 45nm apart in a vacuum. Charge A is +8μC and charge B is -25μC. X is a point 8nm from A.
Calculate the electric field strength at point X only due to A (Ans is 1.2 x 10^9 N/C)
Calculate the overall electric field strength at point X due to A and B. (Ans is 1.32 x 10^9 N/C)
Homework Equations
E = [itex]\frac{1}{4\pi\epsilon}[/itex] X [itex]\frac{Q}{d^{2}}[/itex]
The Attempt at a Solution
Electric field strength due to A.
[itex]\frac{1}{4\pi(8.9X10^-12)}[/itex] X [itex]\frac{8X10^-6}{(8X10^-9)^{2}}[/itex]
= 1.117X10^21
= 1.12X10^21 N/C
Electric Field Strength due to B.
E = [itex]\frac{1}{4\pi(8.9X10^-12)}[/itex] X [itex]\frac{25X10^-6}{(37X10^9)^{2}}[/itex]
= 1.632X10^20
= 1.63X10^20 N/C
1.12X10^21 + 1.63X0^20 = 1.283X10^21 N/C
Where am I going wrong?
I would appreciate any help.