Answer:
434.16 Joules
Explanation:
u = Initial velocity
v = Final velocity
m = Mass of person
From work-energy theorem
[tex]KE=\frac{1}{2}m(v^2-u^2)\\\Rightarrow KE=\frac{1}{2}\times 67\times (3.6^2-0)\\\Rightarrow KE=434.16\ Joules[/tex]
The runner loses 434.16 Joules of mechanical energy.
[tex]W=F\times s\\\Rightarrow F=\frac{W}{s}\\\Rightarrow \mu mg=\frac{W}{s}\\\Rightarrow s=\frac{W}{\mu mg}\\\Rightarrow s=\frac{434.16}{0.7\times 67\times 9.81}\\\Rightarrow s=0.94364\ m[/tex]
He slides 0.94364 m
