Final answer:
Newton's 1st law of motion states that an object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an outside force.
Step-by-step explanation:
The subject of this question is Physics. Specifically, it is referring to Newton's 1st law of motion.
Newton's 1st law of motion states that an object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an outside force.
For example, if you push a book on a table, it will eventually come to a stop because of the friction between the book and the table, which acts as an outside force.
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