# Motion: Average speed and acceleration

Secretariat ran the Kentucky Derby with times of 25.4 s, 24.3 s, 23.1 s, and 22.8 s, for the quarter mile.

(a) Find his average speed during each quarter-mile segment.

first segment -------- ft/s

second segment -------- ft/s

third segment -------- ft/s

fourth segment -------- ft/s

(b) Assuming that Secretariat's instantaneous speed at the finish line was the same as his average speed during the final quarter mile, find his average acceleration for the entire race. (Hint: Recall that horses in the Derby start from rest.)

------- ft/s2

https://brainmass.com/physics/acceleration/motion-average-speed-acceleration-295039

#### Solution Summary

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