Is the electric field and ½ε0|E|2 is the associated energy density. (a) Find the Euler-Lagrange equation for the potential Φ(x) that minimizes the energy within the volume V. Do we recognize this equation?

neither accurate nor precise.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.

because if the tool that you are using is not balanced it there would be false mass.