A charge of #-5 C# is at the origin. How much energy would be applied to or released from a # 4 C# charge if it is moved from # (5 ,-3 ) # to #(1 ,-2 ) #?

1 Answer
Mar 5, 2016

#W~=213*10^9" J"#

Explanation:

#step-1:#
#"Potential at the point of (5,-3) created by charge of -5C:"#
#V_(<5,-3>)=-(k*5)/sqrt(5^2+3^2)=-(5k)/sqrt34#
#"Potential at the point of (1,-2) created by charge of -5C:"#
#V_(<1,-2>)=-(k*5)/sqrt(1^2+2^2)=-(5k)/sqrt 5#
#"work doing by electrical forces between two points:"#
#W=q(V_(<1,-2>)-V_(<5,-3>))#
#W=4(-(5k)/sqrt5+(5k)/sqrt34)#
#W=4*5*k(-sqrt5+sqrt34)/(sqrt5*sqrt34)#
#W=20k*(-2,236+5,831)/(13,038)#
#W=(71,9*k)/(13,038)" "k=9.10^9#
#W~=213*10^9" J"#