rollercoaster track. The height of the first hill is 12.0 m and the speed of the car at the top of the first hill is 2.7 m/s.Find the height of the second hill if the speed at the top of the second hill is 5.5 m/s

Respuesta :

We can use the conservation of energy:

[tex]E1=E2[/tex]

Where:

E1 = Energy of the car in the first hill

E2 = Energy of the car in the second hill

So:

[tex]\begin{gathered} K1+U1=K2+U2 \\ where: \\ K1=\frac{1}{2}mv1^2=\frac{1}{2}m(2.7)^2=3.645m \\ U1=mgh1=9.8(12)m=117.6m \\ K2=\frac{1}{2}mv2^2=\frac{1}{2}m(5.5)^2=15.125m \\ U2=mgh2=9.8mh2 \end{gathered}[/tex]

Therefore:

[tex]3.645m+117.6m=15.125m+9.8mh2[/tex]

Divide both sides by m:

[tex]\begin{gathered} 3.645+117.6=15.125+9.8h2 \\ 121.245=15.125+9.8h2 \\ 106.12=9.8h2 \\ h2=\frac{106.12}{9.8} \\ h2\approx10.829m \end{gathered}[/tex]

Answer:

The height of the second hill is approximately 10.829m