23. Two balls, each with a mass of 2 kg, and velocities of 2 m/s and 3 m/s collide head on. Their final velocities are 3 m/s and 2 m/s respectively. Is this collision elastic or
inelastic? Explain. (use the lab to help answer this question
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Which statement is the best definition of an atom? a) anything that has mass and occupies space. b) the smallest particle that has the properties of an element. c) a substance that cannot be broken down chemically into simpler substances. eliminate d) the smallest unit of a substance that exhibits all of the properties characteristic of that substance.