Seed 4

course Phy 201

I have graphs included for this question. However, they don't appear when I copy and paste. Too bad you can't see it in a word document!

The problem:A ball is moving at 10 cm/s when clock time is 4 seconds, and at 40 cm/s when clock time is 9 seconds.

• Sketch a v vs. t graph and represent these two events by the points (4 sec, 10 cm/s) and (9 s, 40 cm/s).

The sketch of the graph is set up with velocity labeled on the y-axis and clock time labeled on the x-axis. The dots are going in an upward slanted line from left to right. The first point is (4 sec, 10 cm/s) and the second point is (9s, 40 cm/s).

• Sketch a straight line segment between these points.

The straight line between these points is slanting upward from left to right connecting (4 sec, 10 cm/s) and (9s, 40 cm/s)

• What are the rise, run and slope of this segment?

Rise = Vertical coordinates = 40 – 10 = 30

Run = Horizontal coordinates = 9-4 = 5

Slope = 30/5 = 6

Good, but 30 cm/s / (5 s) = 6 (cm/s) / s = 6 cm/s * (1/s) = 6 cm/s^2. You did not include units with your result.

• What is the area of the graph beneath this segment?

Change in position = 40 cm/s – 10 cm/s = 30 cm/s

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The region beneath the graph is a trapezoid.

'What is the average altitude of the trapezoid and what does it represent?

'What is the width of the trapezoid and what does it represent?

'What therefore is the area of the trapezoid and what does it represent?

See my notes. Your last solution requires modification; please submit in the usual manner.