Two charges of # -1 C # and # -3 C# are positioned on a line at points # -2 # and # 7 #, respectively. What is the net force on a charge of # 4 C# at # -1 #?

1 Answer
Feb 5, 2018

The net force is #=37.7*10^9N#

Explanation:

The net force between the charges is

#F=k(Q_1Q_3)/r_1^2+k(Q_2Q_3)/r_2^2#

Where #r# is the distance between the charges

The Coulomb Constant is #k=9*10^9Nm^2/C^2#

The charge #Q_1=-1C# at #(-2,0)#

The charge #Q_2=-3C# at #(7,0)#

The charge #Q_3=4C# at #(-1,0)#

The net force is

#F=910^9*(-1)*(4)/(1)^2+910^9(-3)*(4)/(8)^2=-37.7*10^9N#

The negative sign indicates that the force is attractive