Question

A particle with charge 3 µc is located on the x-axis at the point −10 cm , and a second particle with charge −5 µc is placed on the x-axis at 6 cm . −10−8 −6 −4 −2 2 4 6 8 10 3 µ c − 5 µ c − 7 µ c x → (cm) what is the magnitude of the total electrostatic force on a third particle with charge −7 µc placed on the x-axis at 2 cm ? the coulomb constant is 8.9875 × 109 n · m 2 /c 2 . answer in units of n.

Answer 1

Force on -7 uC charge due to charge placed at x = - 10cm

`F = (kq_1q_2)/(r^2)`

now we will have

`F_1 = ((8.9875 * 10^9)(3\mu C)(7\mu C))/(0.12^2)`

`F_1 = 13.1 N` towards left

similarly force due to -5 uC charge placed at x = 6 cm

`F = (kq_1q_2)/(r^2)`

now we will have

`F_2 = ((8.9875 * 10^9)(5\mu C)(7\mu C))/(0.04^2)`

`F_2 = 196.6 N` towards left

Now net force on 7 uC charge is given as

`F = F_1 + F_2`

`F = 196.6 + 13.1 = 209.7 N`

towards left