Answer:[tex]v_2=9.89 m/s[/tex]
Explanation:
Given
mass of roller coaster (m)=500 kg
Height of high hill=9 m
height of low hill=4 m
As total Energy is conserve therefore
Total Energy at high hill=Total Energy at low hill
Energy =Potential Energy + kinetic Energy
[tex]mgh_1+\frac{mv^2}{2}=mgh_2+\frac{mv_2^2}{2}[/tex]
At top Kinetic energy is zero
[tex]g\times 9+0=g\times 4+\frac{v_2^2}{2}[/tex]
[tex]2\times 5\times g=v_2^2[/tex]
[tex]v_2=\sqrt{2\times 5\times 9.8}[/tex]
[tex]v_2=9.89 m/s[/tex]
