Question

1. (4 points) the graph in the figure shows the position of an object as a function of time. the letters h - l represent particular moments of time. (a) at which moment in time is the speed of the object the greatest? (b) at which moment in time is the speed of the object equal to zero?

Explanation:

Step1: Recall speed - position relationship

Speed is the magnitude of the slope of the position - time graph.

Step2: Find maximum speed

The slope of the position - time graph is the greatest (in magnitude) at point J. So the speed is greatest at J.

Step3: Find zero speed

The slope of the position - time graph is zero at the peak of the curve (where the tangent to the curve is horizontal). This occurs at point I.

Answer:

(a) J
(b) I