A charge of #3 C# is at #(3, -1 )# and a charge of #-4 C# is at #( -3, 7 )#. If both coordinates are in meters, what is the force between the charges?

1 Answer
Jul 6, 2018

Answer:

#F=-1.08*10^9 N#

Explanation:

Charge #q_1=3C# is placed at #(3,-1)#
Charge #q_2=-4C# is placed at #(-3,7)#

Distance between both charges is
#r=sqrt((x_2-x_1)^2+(y_2-y_1)^2#
#r=sqrt((-3-(3))^2+(7-(-1))^2#
#r=sqrt((-6)^2+(8)^2#
#r=sqrt(36+64)#
#r=sqrt(100) m = 10 m# and #r^2=100#

Force between two charges #q_1# and #q_2# is
#F=(kq_1q_2)/r^2 # where #k=9*10^9 Nm^2/C^2#
#=>F=((9*10^9)(3)(-4))/(100)#
#=>F=((9*10^9)(-12))/(100)#
#=>F=((-108*10^9))/(100) N#
#=>F=-1.08*10^9 N#