Given that the mass of the runner, m = 60 kg
The kinetic energy of the runner, K.E. = 480 J
To find the speed of the runner, v
Kinetic energy is given by the formula
[tex]K\mathrm{}E\mathrm{}=\text{ }\frac{1}{2}mv^2[/tex]Substituting the known values, speed will be
[tex]\begin{gathered} v=\sqrt[]{\frac{2\times K.E.}{m}} \\ =\sqrt[]{\frac{2\times480}{60}} \\ =4\text{ m/s} \end{gathered}[/tex]Thus the speed of the runner is 4 m/s.
