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III Careful measurements have been made of Olympic sprinter in the 100 meter dash. A quite realistic model is that the sprinter's velocity is given by
where t is in s, vxis in m/s, and the constants a and b are characteristic of the sprinter. Sprinter Carl Lewis's run at the 1987 World Championships is modeled with a = 11.81 m/s and
- What was Lewis's acceleration at t = 0 s, 2.00 s, and 4.00 s?
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Chapter 2 Solutions
Physics for Scientists and Engineers: A Strategic Approach with Modern Physics, Books a la Carte Edition; Student Workbook for Physics for Scientists ... eText -- ValuePack Access Card (4th Edition)
- A garden snail named Archie, owned by Carl Branhorn of Pott Row, England, covered a 33-cm course in 2.0 min at the 1995 World Snail Racing Championships, held in Longhan, England (Fig. P1.13). Determine Archies average speed Sav = d/t in the appropriate SI units.arrow_forwardMario rides his motorcycle in going to school. He drives at an average speed of 30 kilometers per hour. The distance between his house and the school is 15 kilometers. Every time he sees his best friend Jessica walking on the road, he invites her for a ride and lowers his speed. On the other hand, he increases his speed when he wakes up late for school. a) If x represents the time it takes Mario to drive to school with the given distance of 15 kilometers, how will you represent the relationship of his speed (y) versus the time (x)?arrow_forwardO Aurora and Norma decide to walk to school. They must walk 3 kilometers south on one street and then 2 kilometers west on another to get to their school. If they could have walked directly to school from home, without following streets, how many kilometers would their trip have been? O 3.6 km O 3.3 km O 2.2 km O 2.5 km Submit Answer 1. C DELL O ✓ 4 INTLOarrow_forward
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- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning