Question

Two charges of `-3 C` and `4 C` are positioned on a line at points `-3` and `4`, respectively. What is the net force on a charge of `7 C` at `6`?

Answer 1

`F_"net"=60,66*10^9 N`

Explanation:

`"The force between two charges is given by Coulomb's formula: "`
`F=k*(q_1*q_2)/d^2" "k=9*19^9`
`"The force between A and C is :"F_(AC)" (the blue vector)"`
`"The Force between B and C is :"F_(BC)" (the red vector)"`
`F_(AC)=k((-3)*7)/9^2=-(21k)/81`
`F_(BC)=k*(4*7)/2^2=(28k)/4`
`"Net Force on a charge of 7C:"F_"net"=F_(AC)+F_(BC)`
`F_"net"=-(21k)/81+(28k)/4`
`F_"net"=k(28/4-21/81)`
`F_"net"=2184/324*k`
`F_"net"=6,74*k`
`F_"net"=6,74*9.10^9`
`F_"net"=60,66*10^9 N`