how to find change in velocity with my speed data?
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Answer:
ΔV = 9
Explanation:
Given your speed data, we can simply think about it graphically and calculate the slope. When your data is layed out on a graph there is a linear relationship, so it has a constant slope. We can calculate slope easily with your data using y2-y1/x2-x1 so 18-9/2-1. This gets us a constant change in velocity (slope) of 9.