Question

A cockroach named Cicero and a spider named Susan are playing tag with each other. The “rightward" direction is taken as the positive x-direction along the pipe. The following plot gives the velocity versus time for bothCicero (solid line) and Susan (dotted line).

We also happen to know that Cicero starts at the origin at time t = 0, and Susan starts 9 cm to the left of Cicero. The period of time depicted on the plot is divided into four stages labeled I, II, III, IV, and V.

2.1. Consider each of the following descriptions of Cicero and Susan’s motions which you can read as starting with the statement “Cicero and Susan...”

A. are running to the right B. are running to the left

C. are speeding up D. are slowing down

E. have constant speed
F. have increasing velocity vx

G. have decreasing velocity vx
H. have increasing acceleration ax

I. have decreasing acceleration ax

J. have constant acceleration ax

K. have positive acceleration ax

L. have negative acceleration ax

For each of five stages, identify all of the above statements A - L that apply by listing their corresponding letters on the blank line.

Stage I.

Stage II.

Stage III.

Stage IV.

Stage V.

2.2. Determine the accelerations ax of both Cicero and Susan during each stage. Include both the value and the appropriate unit.

2.3. Calculate the positions of both Cicero and Susan at the end of each stage. Include both the value and the appropriate unit.

2.4. Plot the acceleration versus time for both Cicero and Susan for all five stages on the same plot. Use a dotted line for Susan and a solid line for Cicero. Make sure your plot both has the correct shape and is as numerically accurate as possible. Include labels on your axes, units, and tick marks with values that define the scale of each axis.

2.5. Plot the position versus time for both Cicero and Susan for all five stages on the same plot. Use a dotted line for Susan and a solid line for Cicero. Make sure your plot both has the correct shape and is as numerically accurate as possible. Include labels on your axes, units, and tick marks with values that define the scale of each axis.

(em/5 1O 15

Answer 1

Stage I - F, J and K for both. Because speed is uniformly increasing

Stage -II - E for both. Because horizontal graph

Stage III - G,J and L for both. Because speed decreasing uniformly

Stage iV - Same as above

Stage V - F, J and K for both, As speed increases, accn is +ve