Two charges of # -1 C # and # 9 C# are positioned on a line at points # 1 # and # 7 #, respectively. What is the net force on a charge of # -3 C# at # 2 #?

1 Answer
Mar 1, 2018

The net force is #=17.28*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 #(1,0)#

The charge #Q_2=9C# at #(7,0)#

The charge #Q_3=-3C# at #(2,0)#

The net force is

# F = 910^9*(-1)*(-3) / (1)^2+910^9(-3)*(9)/(5)^2 = 17.28*10^9N#

The positive sign indicates that the force is repulsive