Three particles each of mass 100 gm are brought from a very large distance to the vertices of an equilateral triangle whose side is 20 cm in length. The work done will be : 

-1.00 x 10^-11 Joule

Potential energy of three particles system

\(U = -\frac{GMm}{r_{12}}-\frac{GMm}{r_{23}}-\frac{GMm}{r_{31}}\)

Given : \([m_1 = m_2 = m_3 = 100 \text{ g and } r_{12} = r_{23} = r_{31} = 2 \text{ cm}]\)

\(\Rightarrow U = 3[\frac{-6.67*10^{-11}*10^{-1}*10^{-1}}{20*10^{-2}}]\)

  = - 1.00 x 10^-11 J