Respuesta :
If the boy started at rest then its speed would be equal to 4.5 m/s squared.
Answer:
The speed of boy is 4.5 m/s
Explanation:
Given that,
Kinetic energy = 810 J
Mass = 80 kg
We need to calculate the speed
Using formula of kinetic energy
[tex]K.E=\dfrac{1}{2}mv^2[/tex]
Where, m = mass
v = speed
Put the value into the formula
[tex]810=\dfrac{1}{2}\times80\times v^2[/tex]
[tex]v^2=\dfrac{2\times810}{80}[/tex]
[tex]v=\sqrt{\dfrac{2\times810}{80}}[/tex]
[tex]v=4.5\ m/s[/tex]
Hence, The speed of boy is 4.5 m/s.
