Laws of conservation of linear and angular momentum can be derived from Newton's laws of motion in mechanics. Are they valid beyond mechanics?

Explanation

To answer the question regarding the validity of the laws of conservation of linear and angular momentum beyond mechanics, we can break down the solution into several steps:

### Step 1: Understanding Conservation Laws
The laws of conservation of linear and angular momentum state that in an isolated system, the total linear momentum and total angular momentum remain constant over time, provided no external forces or torques act on the system.

### Step 2: Derivation from Newton's Laws
These conservation laws can be derived from Newton's laws of motion. Specifically, Newton's second law, which states that the force acting on an object is equal to the rate of change of its momentum, leads to the conclusion that if no net external force acts on a system, the momentum remains constant.

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