An athlete finished the 100 meter race in 10sec. What was his average speed? acceleration? Acceleration time? Acceleration distance
Help with few questions already got the
already got the first two
V=d/t
=100m/10s
=10m/s
and
Acceleration= Vf-Vi/t
=10m/s-0/10s
=10m/s^2
how to find the other two, the acceleration time and the acceleration distance? please help
2 answers
The teacher also give the athlete's top speed to be 12m/s, dunno if this will be helpful, but still need to reconsider I guess
He clearly did not accelerate at 10 m/s^2 for the whole 10 seconds, or the distance covered would have been 1/2 at^2 = 500m and his top speed would have been 100m/s.
So, if he accelerated smoothly from 0-12 m/s over t seconds, then a = 12/t m/s^2
So we have
(1/2)(12/t)t^2 + 12(10-t) = 100
6t+120-12t = 100
-6t = -20
t = 10/3 s
He accelerated for 10/3 seconds at 18/5 m/s^2
So, if he accelerated smoothly from 0-12 m/s over t seconds, then a = 12/t m/s^2
So we have
(1/2)(12/t)t^2 + 12(10-t) = 100
6t+120-12t = 100
-6t = -20
t = 10/3 s
He accelerated for 10/3 seconds at 18/5 m/s^2
1 answer