Which of these is equivalent to the law of conservation of energy?
a. the total mechanical energy is always conserved.
b. friction is a nonconservative force.
c. kinetic energy can be transformed into thermal energy.
d. the total energy of all types remains the same in a closed system.

The Law of the Conservation of Energy is stating that the total mechanical energy is always conserved or in simpler terms, not used or saved.

The correct option A.

Explanation:

Law of conservation of energy states that energy can neither be created nor be destroyed. But it can be transformed from one form to another.Law of conservation of Mechanical energy  states that mechanical energy of the closed system remain constant until dissipative forces are absent. This means that potential energy gets converted in kinetic energy or vice versa.

Mechanical energy is defined as the sum of the both potential and kinetic energies.

M.E = P.E + K.E

So, from the given options the correct answer is option A.

What are your choices. i believe it might be mitochondria but i will know for sure when i see the choices. let me know okay i'm happy to answer

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