A Little History on Roller Coasters • Pictured here is La Marcus Thompson’s Switchback Railway • It was built in 1890 and is said to be the early “true roller coaster.” • To ride the coaster, riders needed to first climb a flight of stairs to board the coaster, once they were in, the coaster was off to a blazing speed (not velocity) of 6 mph down the track. This roller coaster had no engines and accelerated simply from an initial push, changes in the slope of the track and the force of gravity. The ride would run out of momentum at the other end of the tracks and the riders would get off, climb another tower at the other end, board a different cart and be pushed off back to the starting tower.
Take a look at this Coaster What factors acting on this background coaster were also acting onLa Marcus Thompson’s Switchback Railway? • Speed • Velocity • Acceleration • Momentum • Gravity Let’s differentiate between them!
Precautionary Slide(Just in case our last slide didn’t go so well.) • Speed and Velocity are very similar. Both are measured in m/s, however, velocity also includes a set direction. Any change in Direction, is a change in velocity, but not always a change in speed. • Acceleration is simply the rate at which either speed or velocity changes. • Momentum is another term related to velocity. It is the force the occurs from the combination of velocity and mass. The greater an objects momentum, the harder it is to stop. Think of Jaugernaut from the last X-men movie. (X2 was the best!)
Other Forces in Action • Although the Switchback Railway was very basic and not the most exciting, it incorporated a few more forces as well as some principals. • Would you believe that the extremely fast 6 mph roller coaster actually exerted over 2 G’s of force? I wouldn’t believe it either, that’s why you shouldn’t use Wikipedia for research.
Question: So what is a “G” or a “G-Force”? • Answer (in honor of Savoca) • A “G” or “G-Force” is a unit of acceleration equal to the acceleration caused by gravity. A freefalling object falls with a force equal to 1 G or a rate of 9.8 m/s per second. • Keep in mind, gravity is an attraction between two objects with mass. The earth is not the only object that has gravity. • Let’s demonstrate the differences between the different levels of G-forces!
Conservation of Energy • This law simply states that the total amount of energy in an isolated system remains constant over time. • The only thing that can happen to energy in a closed system is that it can change form. In our case Potential Energy goes to Kinetic Energy to Potential Energy to Kinetic Energy and so on…
Conservation of Energy Continued… • This law, when applied to our Roller Coasters, is very similar to that of Galileo’s Stop Theory (think back to the rolling marble in the video). • He said that the object on the track would never go higher than it’s original height or lower than it’s original height unless acted on by other forces. These forces can include friction, air resistance and so on. • Let’s test this out!
Stop Height and Newton’s 2nd Law isn’t always a good thing! • A few of you have told me you have ridden Kingda Ka. Unfortunately the designers of this ride failed to take into account the fact that the greater the mass the less an object will accelerate if the forces on the object do not change. Let’s check out this Epic Fail!!!
Your Roller Coasters! • This video as well as our demonstration, should just go to show you the importance of the conservation of energy and stop height, when designing your coasters. No hill should be higher than the previous hill!
Time to make some CENTS out of this! • CENTripetal Force – Acceleration that occurs in a circular motion. • CENTrifugal Force – The apparent force, equal and opposite to the centripetal force. The force acts towards the center of the cirle.