# AP physics

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Lucy is using a programmable treadmill. She inputs a top speed into the treadmill and presses "start." The treadmill

accelerates from rest at 0.100 m/s2 until it reaches that speed, after which it stays at that constant speed. Later, when she is
getting tired, she hits the "stop" button and the treadmill slows down at a rate of 0.200 m/s2 until it comes to a stop. The
treadmill tells her that she traveled the equivalent of 3.00 kilometers in 15.0 minutes while the treadmill was in motion. (a) If
Lucy had been running forward in a straight line on the ground (instead of in place on the treadmill), what would be her
average velocity in meters per second over the whole 15.0 minutes? (b) What would be her average acceleration over the
15.0 minutes? (c) What was the top speed of the treadmill? (d) How long after pressing "start" did she press "stop?"

I got a and b to be 3.3m/s and 0 m/s^2 respectively, but the next part is too hard. If you can guide me through it, it would mean a lot