Question
Emew2Problem 2.26 tems 1. Problem 2.04 2. Problem 2.09 3 Problem 2,12 4 Problem 2.22 5 Chapter 2 Q 6. Problem 226 7. Problem 2,40 8 Problem 2.39 9. Chapter 2Q 10 Probiem 2 4 11. Chapter 2 Q « previous 6 of 11 nexts Problem 2.26 Part A A world-class sprinter can reach a top speed (of about 11.6 m/s ) in the first 20.0 m of a race What is the average acceleration of this sprinter? Express your answer with the appropriate units. aValue Units Submit My Answers Give Up Incorrect; Try Again; 5 attempts remaining Part B How long does it take her to reach that speed? Express your answer with the appropriate units. I t = Value Units
Explanation / Answer
Initial velocity u = 0
Final velocity v = 11.6 m/s
Distance S = 20m
A) Using:
v^2 = u^2 +2aS
=> a = (v^2-u^2)/2S = (11.6^2 - 0)/(2 x 20) = 3.364 m/s2
B)
Using:
v = u + at
=> t = (v-u)/a = (11.6 - 0)/3.364 = 3.45s