WEBVTT

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Here is the problem: What is the momentum of a 0.145 kg object moving at 40 m/s?

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Use the momentum formula, rearranged for the unknown, in SI units.

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Formula: momentum.

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Substitute the known values.

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So the answer is momentum p equals 5.8 kg times m/s.

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Momentum is a vector with the same direction as the velocity; in one dimension the sign shows the direction. A 1000 kg car at 20 m/s and a 10 kg ball at 2000 m/s carry the same momentum.

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Substituted every value back into the formula: both sides agree, which checks out.