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

1 Answer
Jan 22, 2018

Answer:

#28.68×10^9# N along negative #X# axis

Explanation:

Here, the #-5C# charge at #x=5# tries to push the #-5C# charge at #x=0#

And the value of that force is #F1# = #9×10^9×(-5)×(-5)/(5^2) N# or #9×10^9 N#

The #-7C# charge at #x=4# also tries to push it away due to repulsion in the same direction.

And,the value of that force is #F2 = 9×10^9×(-7)×(-5)/(4^2) N# i.e #19.68×10^9 N#

So,total repulsive force towards negative #X# axis is #F1+F2# i.e #(9+19.68)×10^9 N# or #28.68×10^9 N#