Three point charges lie in a straight line along the y-axis. A charge of q1 = − 9.0 μC is at y = 6.0 m, and a charge of q2 = −8.0 μC is at y = − 4.0m. The net electric force on the third point charge is zero. Where is this charge located?
llm
Answered on
Answer: -4m
Explanation:
Given q1=-9*10^-6C at r1=6m
And q2=-8*10^-6C at r2=-4m
The force between q1and q2
F12=Kq1q2/r^2
Were r= r1+r2=6-4=2m
F12=9*10^9*9*10^-6*8*10^-6/2^2=0.162N
Note:Fnet=F12+F13 but Fnet==0
Hence F13=Fnet-F12=0-0.162=-.162N
Now
r13=Kq1*q2/F13
=(9*10^9*10^-6*8*10^-6)/-.162
r13=-4m