Question

error analysis the graph shows the speed of a bicycle rider during her evening ride.
a. a student incorrectly claimed that there are 3 constant intervals defined in the graph. how many constant intervals are there? what error might the student have made?
b. how are the constant intervals alike?
c. how are the constant intervals different?
what error might the student have made?
a. the student counted the number of increasing and decreasing intervals.
b. the student counted the number of decreasing intervals.
c. the student counted the number of increasing intervals.
b. how are the constant intervals alike?
a. all of the constant intervals indicate lengths of time when the speed is constant.
b. all of the constant intervals indicate lengths of time when the speed is increasing.
c. all of the constant intervals indicate lengths of time when the speed is decreasing.

Explanation:

Step1: Identify constant intervals

A constant interval on a speed - time graph is where the graph is a horizontal line. Looking at the graph, there are 2 constant intervals.

Step2: Analyze student's error

A constant interval is a horizontal line. The student might have counted the number of increasing and decreasing intervals instead of the horizontal (constant) ones. For part (b), by definition, a constant interval means the speed does not change over that time interval.

Answer:

a. There are 2 constant intervals. The student counted the number of increasing and decreasing intervals (Option A).
b. All of the constant intervals indicate lengths of time when the speed is constant (Option A).