Three particles, each having a charge of `10 mu C` are placed at the coners of an equilateral triangle of side `10 cm`. The electrostatic potential energy of the system is (Given `(1)/(4pi epsilon_(0)) = 9 xx 10^(9)N-m^(2)//C^(2))`

Options

A. Zero
B. `oo`
C. 27 J
D. 100 J

Answer

C

Explanation

For a pair of charges
`U=(1)/(4piepsi_(0))(1_(1)q_(2))/(r)`
`U_("System")=(1)/(4pi epsi_(0))[(10xx10^(-6)xx10xx10^(-6))/(10//100)+(10xx10^(-6)xx10xx10^(-6))/(10//100)]`
`=3xx9xx10^(9)xx(100xx1^(-12)xx100)/(10)=27J`