Two charges of # -5 C # and # -3 C# are positioned on a line at points # 7 # and # 4 #, respectively. What is the net force on a charge of # -1 C# at # 0 #?

1 Answer
Jan 27, 2018

The net force is #=2.61*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=-5C# at #(7,0)#

The charge #Q_2=-3C# at #(4,0)#

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

The net force is

#F=910^9*(-5)*(-1)/(7)^2+910^9(-3)*(-1)/(4)^2=2.61*10^9N#

The positive sign indicates that the force is repulsive