Question

physics,

can you please help me solve this
https://www.dropbox.com/s/8uwrpl0h3fcm1r8/Screenshot%202015-12-13%2018.58.35.png?dl=0

Answer 1

hint:
we can compute the acceleration of the sprinter, in order to do that, we can apply this formula:
\[\huge d = \frac{{{v^2}}}{{2a}}\]
where \(d=12\), and \(v=11\)

Answer 2

after that, we can compute the requested time \(t\), using this formula:
\[\huge t = \frac{v}{a} + \frac{{S - d}}{v}\]
where \(S=100\)
since the second part of the motion of the sprinter is a uniform motion

Answer 3

I got the answer I am just not sure if it's correct