Final answer:
Both statements A and B are true. Relativistic mechanics, a part of Einstein's theory of relativity, provides a more accurate description for objects travelling at speeds close to the speed of light, compared to Newtonian mechanics. Quantum mechanics is required when dealing with objects of a size comparable to an atom, where it is more accurate than Newtonian mechanics.
Step-by-step explanation:
The question is asking whether statement (A) which asserts that Relativistic mechanics is more accurate than Newtonian mechanics, and statement (B) that posits Quantum mechanics is more accurate than Newtonian mechanics when the masses involved are comparable with the mass of an atom, are true or false. Let's analyze each statement individually using the principles of modern physics.
In statement (A), Relativistic mechanics, which is part of Einstein's theory of relativity, indeed offers a more accurate description for objects traveling at speeds near to the speed of light compared to Newtonian mechanics, thus making statement (A) true.
The second statement (B) involves the realm of quantum mechanics. Quantum mechanics is required to accurately describe phenomena at atomic and subatomic scale, i.e., when the masses are comparable to the mass of an atom, making statement (B) also true. It is important to remember, however, that Newtonian mechanics works well for macroscopic objects moving at slow speeds, and remains a good approximation for such conditions.
So, the appropriate answer is (c) Both A & B are true.
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