Posted by **Phil** on Thursday, September 16, 2010 at 1:25am.

A sprinter starts from rest in a 100-meter race, accelerates to his full running speed of 10.3 m/s in 1.15 seconds (assume constant acceleration) and continues at that speed for the rest of the race.

(a) How far did he run before attaining his full speed?

(b) What was his final time for the race?

- Physics -
**TutorCat**, Thursday, September 16, 2010 at 1:31am
(a)

acceleration=(final velocity-initial velocity)/time

distance = (1/2)*(acceleration)*(time)^2 + (initial velocity)*(time)

(b) 100m - _____ (<-answer from (a))

find time using this formula:

distance = (1/2)*(acceleration)*(time)^2 + (initial velocity)*(time)

finally, add that time with 1.15 seconds

- Physics -
**TutorCat**, Thursday, September 16, 2010 at 1:32am
note: for part (b) plug in the "new" distance

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