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Here is the problem: A 40 kg cart accelerates at 4.5 m/s squared. What net force acts on it?

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Use the Newton prime s second law formula, rearranged for the unknown, in SI units.

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Formula: Newton prime s second law.

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Substitute the known values.

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So the answer is net force F equals 180 N.

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Newton prime s second law links the net force on an object to its acceleration: F equals ma. Force and acceleration point the same way, so a negative force gives a negative acceleration. One newton accelerates one kilogram by 1 m/s squared.

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