posted by Harry please please .
Amber visits a theme park that has a roller coaster that travels upside down. Which of the following is the best explanation for why the roller coaster car stays in contact with the track when it travels upside down?
A)The track and car are held together by a series of strong magnets.
B)The car has large amounts of thermal energy that binds it to the track.
C)The car has chemical energy that resists the effect of gravity when it is upside down.
D)The car has mechanical energy and is fast enough that gravity cannot pull the car down.
D because mechanical energy is basically kinetic energy and when that is greater than the force of gravity then it will not fall down.