physics
posted by JohnX .
Olympic champion Justin gaitlin set a new world record for 100.0 m sprint at the last lympics by clocking 9.86 s for the race.Calculate
a)His average speed for the race
b)Assuming that he accelerated uniformly for the first 4.86 s after taking off the blocks to reach a maximum speed Vmax with which he continues for the rest of the race, is this speed likely to be same as, less than, or greater than the average speed.Why?
c)calculate the max. speed he reaches at the end of the first stage of his motion
d)Calculate the distance covered during the two stages and the steady acceleration in the first stage.

Surely you can do (a) yourself.
For (b), consider if the average speed could ever exceed the maximum speed, and in what situation they could be the same.
For (c), the average speed during acceleration is Vmax/2 and the total distance travelled is
(Vmax/2)*4.86 s + Vmax*5.00 s. Set this equal to 100 m and solve for Vmax
I will be happy to critique your work on (d)
Respond to this Question
Similar Questions

math
What would be the answer to85x205=960x3256 85 x 205 = 17425 960 x 3256 = 3125760 They aren't equal. Sorry. =( WAT ARE YOU ASKING EXACTLY The longest oneday bike race goes from Bordeaux, france, to paris, france. the record for this … 
physics
Olympic champion Justin gaitlin set a new world record for 100.0 m sprint at the last lympics by clocking 9.86 s for the race.Calculate a)His average speed for the race b)Assuming that he accelerated uniformly for the first 4.86 s … 
Physics Again
In 1954 the English runner Roger Bannister broke the four minute barrier for the mile with a time of 3:59.4s (3 min and 59.4 sec) In 1999 the Morroccan runner Hicham set a record of 3:43.13s for the mile. If these two runners had run … 
Physics
If 100 m sprinters accelerate from rest for 3.5 s at 2.8 m/s^2, how far have they run to this point? 
Physics
The Yukon Quest, an annual dogsled race between Whitehorse in the Yukon and Fairbanks in Alaska, covers a gruelling distance of 1.61 × 103 km. Assuming that the average speed of the dog team that set a course record is 6.28 km/h, … 
Physics
The best sprinters can run a 100 m in 10.0 s. A 77.2 kg sprinter accelerates uniformly for the first 51.0 m to reach top speed, which he maintains for the remaining 49.0 m. What is the average horizontal component of force exerted … 
physics
(a)The world record for the 100meter dash is 9.58 seconds (Bolt, 2009). Use the speed from part (a) as his maximum velocity. Assume a sprinter accelerates at a constant rate up to their maximum velocity, which is maintained for the … 
physics
(a) In 2009, Usain Bolt ran the last 100 meters of the 150meter race in 8.70 seconds. What is Usain Bolt’s speed? 
physics
(a) In 2009, Usain Bolt ran the last 100 meters of the 150meter race in 8.70 seconds. What is Usain Bolt’s speed? 
Physics
usain bolt set the world record for the 100m dash, proving to be the fastest man in history, with a time of 9.58s. what was bolt's average speed in miles per hour?