Which of the following real-world examples models linear motion? a. throwing a rock in the air at a 60-degree angle b. running around the curve of a track c. throwing a rock in the air at a 45-degree angle d. running 50 m along a straight track

D. Running 50 m along a straight track

Explanation:

Running 50 m along a straight track is a real-world example of linear motion.

Linear motion means moving along a (straight) line, a direct and straight line from point A to point B.

All the other proposed answers (A,B,C) involve a curve.  The two rock examples will curve due to gravity and running around a curve on a track isn't a straight line.

I hope that helps you understanding the principle of linear motion.

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