Double Helix in Roller Coaster

[bigtymer031]

Homework Statement

When riding a roller coaster, when you enter a double helix why does it feel as if you're speeding up? I'm in the rotational dynamics section, so the answer will most likely be about Conservation of Angular Momentum or something along those lines. I am really interested but I just can't feel confident about any of my answers.

Homework Equations

The Attempt at a Solution

It is because the conservation of Angular Momentum, it gives the allusion of the roller coaster speeding up.

 

[jbsteele]

As the coaster enters the double helix, the radius of the track decreases, since the coaster is traveling in a curved path. This decrease in radius causes the coaster to speed up, as the change in angular momentum is equal to the torque multiplied by the time interval. Therefore, as the radius decreases, the angular momentum remains constant and the velocity increases. This gives the allusion of the roller coaster speeding up.