Question

A roller coaster car with a mass of 17,690 kg is moving at a speed of 5 m/s over a hill that is 87.4 m above the

Answer 1

Answer:

$E=1.53\times 10^7\ J$

Explanation:

Given that,

The mass of the car, m = 17,690 kg

The speed of the car over the hill, v = 5 m/s

The car is 87.4 m above the  ground.

We need to find the total mechanical energy of the car-Earth system. Mechanical energy is equal to the sum of kinetic energy and potential energy. So,

$E=mgh+\dfrac{1}{2}mv^2\\\\E=17690\times 9.8\times 87.4+\dfrac{1}{2}\times 17690 \times (5)^2\\\\E=1.53\times 10^7\ J$

So, the total mechanical energy of the car-Earth system is $1.53\times 10^7\ J$.