Posted by ty on Thursday, December 20, 2012 at 10:00am.
2 runners accelerate from rest to their top speeds. The 1st runner pat has an acceleration of 5.9 m/s^2 and reaches her top speed in 4 sec. The second runner steven accelerates at 4.4m/s^2 and takes 6.5 sec to reach his top speed the 2 runners run flat out for the remainder of the race they stay at their top speed if the race is the 200m who wins and with what time do they finish?

physics  Elena, Thursday, December 20, 2012 at 10:40am
v1=a1•t1=5.9•4=23.6 m/s
v2= a2•t2 = 4.4•6.5 = 28.6 m/s
τ1 =s/v1 =200/23.6=8.47 s.
τ2 =s/v2 =200/28.6=6.99 s
the total time
for the 1st runner 4+8.47 = 12.47 s.
fir the 2nd runner 6.5+6.99 = 13.49 s