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.oooo T-Mobile 11:22 AM 96%) a session.masteringphysics.com C Physics 195 8AM Spring 2016 Problem 11.34 A 60 kg sprinter, starting from rest, runs 55 m in 7.0s at constant acceleration Part A What is the magnitude of the horizontall force acting on the sprinter? Express your answer to two significant figures and include the appropriate units. F-1308 My Answers Give Up Part B What is the sprinter\'s power output at 2.08,4.0 s, and 6.0 s? Express your answers using two significant figures separated by commas r29.15,9.7 kW SubmitMy Answers Give Up Incorrect: Try Again; 5 attempts remaining

Solution

constant acceleration e = 1/2 a * t²

e = 55 m , t = 7 s

a = 2 e / t² = 55 * 2 / 49 = 2.24 m/s²

F = m * a = 60 * 2.24 = 135 N

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2.0 s

e = 0.5 a * 4 = 4.48 m

W = F * 4.48 = 605 J

P = 416.32 / 2 = 302.4 W

4.0 s

e = 0.5 a * 16 = 17.92 m

W = F * 17.92 = 2419 J

P = 2419 / 4 =604.8 W

6.0 s

e = 0.5 a * 36 = 40.32 m

W = F * 40.32 = 5443 J

P = 5443 / 6 = 907.2 W