Question

Two charges of `2 C` and `-3 C` are positioned on a line at points `-9` and `2`, respectively. What is the net force on a charge of `-1 C` at `-2`?

Answer 1

`F_C=2,05*10^9 " N"`

Explanation:

`"Force between A and C is:"`
`vec F_"AC"=k*(2*(-1))/7^2=-(2k)/49`
`"Force between B and C is:"`
`vec F_"BC"=k*((-3)(-1))/4^2=(3k)/16`
`"both the red and blue vectors is the same direction"`
`vec F_C=vec F_"AC" + vec F_"BC"`

`F_C=(2k)/49 +(3k)/16`

`F_C=(32k+147k)/(49*16)`

`F_C=(179k)/784" "k=9.10^9`

`F_C=(179*9*10^9)/784`

`F_C=2,05*10^9 " N"`