Question

Obtain an expression for law of conservation of energy ?

Answer 1

Law of conservation of energy has no specific expression (as there are so many kinds of energies to deal with) but we know that its true.

However we certainly have the expression of the Law of Conservation of mechanical energy (ME), which is the sum of potential (PE) and kinetic (KE) energies.

so,

PE1 + KE1 = PE2 +KE2

where 1 and 2 denote initial and final.

so, initial ME = final ME