Question

Three point charges are arranged on a line. Charge q3=+5.00x10^-9C and is at the origin. Charge q2=-3.00x10^-9C and is at x=+4.00cm. Charge q1 is at x=+2.00cm. What is the magnitude and sign (+ or -) for q1 if the net force on q3 is zero?

A. 0.750 nC
B. 0.520 nC
C. 0.975 nC
D. 0.000 nC

Answer 1

The answer is 0.750 NC

Step-by-step explanation:

I'm on the same test as well

Answer 2

A. 0.750 nC

Step-by-step explanation:

It is given that net electric force at q3 is 0,

So electric field because of q1 at origin= electric field because of q2 at origin

`k(q_(1) )/(r_(1) ^(2) ) =k(q_(2) )/(r_(2) ^(2) )`

`(q_(1) )/(r_(1) ^(2) ) =(q_(2) )/(r_(2) ^(2) )`

`{q_(1) } } =(q_(2) )/(r_(2) ^(2) )*{r_(1) ^(2)`

=( -3.00x10^-9 x 2^2)/ 4^2

=-0.750nC

It will have negative charge