Respuesta :
Answer:
a. 9m/s b. 27m, 67m c. 53.5m
Step-by-step explanation:
we have 6 seconds of acceleration linear motion and 4 seconds of constant velocity linear motion.
after the first 6 seconds he is 40 meters from the starting line, the he reaches his max speed and after 4 seconds he is 76-40=36 meters from the point he started running max speed
then, max speed
[tex]v=\frac{x}{t} =\frac{36m}{4sec} =9m/s[/tex]
v=9m/s
if he runs for an additional 3 seconds after reaching his max speed
[tex]x=v.t=9m/s . 3sec=27m[/tex]
x=27m
then, distance from the starting line 9 seconds after the race started
[tex]X=40m+x=40m+27m=67m[/tex]
X=67m
if he runs for an additional 1.5 seconds after reaching his max speed (7.5 from the starting line)
[tex]x=v.t=9m/s . 1.5sec=27m[/tex]
x=13.5m
then, distance from the starting line 9 seconds after the race started
[tex]X=40m+x=40m+13.5m=53.5m[/tex]
X=53.5m