Final answer:
The potential energy of the system of three equal point charges is approximately 2.32 x 10^-3 J.
Step-by-step explanation:
The potential energy of a system of three equal point charges can be calculated using the formula:
Potential energy = k * Q^2 / r
Where k is the electrostatic constant (8.99 x 10^9 N*m^2/C^2), Q is the charge, and r is the distance between the charges.
In this case, each point charge is 1.40µC and the distance between them is 0.300m.
Plugging these values into the formula, we get:
Potential energy = (8.99 x 10^9 N*m^2/C^2) * (1.40 x 10^-6 C)^2 / 0.300m
Simplifying, we find that the potential energy of the system is approximately 2.32 x 10^-3 J.