Physics-
General
Easy
Question
To charges 
and 
are placed 
apart, shown in the figure. A third charge 
is moved along the arc of a circle of radius 40cm from C to D. The change in the potential energy of the system is 
, where k is
The correct answer is:
Change in potential energy (DU) = Uf – Ui
Þ 
Þ 
\ k = 8q2
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