Calculate the Sprinter's Final Speed at the Finish Line

[nerdgirl909]

Homework Statement

A sprinter can accelerate with constant acceleration for 3.40 s before reaching top speed. He can run the 100-meter dash in 10 s.

What is his speed as he crosses the finish line? (in m/s)

Homework Equations

kinematic equations

The Attempt at a Solution

a (acceleration) is positive and nonzero for the first 3.40 s

a is zero for the last 6.60 s

 

[learningphysics]

What is the distance covered in the first 3.40s? What is the distance covered in the last 6.60s ?

 

[bugbug]

http://img206.imageshack.us/img206/4810/solin6.th.jpg I think that this is how you would solve this. The distance can be found because it is a case of two equtions and two unknowns.