Carousel Physics H 1 W June 2007

Carousel Physics H 1 W June 2007

Outline • • • Conscious Commuting Carousel History Questions and Calculations Horizontal Accelerometer Summary Sheet Reflection

Conscious Commuting Force on 20 mph. kg = 42. 27 kg 2 95 lb. 0. 44 m/s = 8. 8 m/s Convert me in Mythe weight Find the bus 0 to(42. 27 kg)(9. 8 m/s 2= = 414. 25 N 8. 8 m/s – 12 seconds 20 mph in 0 m/s mph 0. 733 m/s when 2. 2 lb ) 1 to m/s: Newtons: acceleration: 12 s – 0 s begins to move: (42. 27 kg)(0. 733 m/s 2) = 30. 99 N

Conscious Commuting When you eyes isstarts up do you feel thrown traveling how can you speed When the busare closed, at a constant tell when If the bus do the busoras if you are corner? you feel backward? forward goes around a moving? You do can tell becauseto acceleratebecause or When not feel begins you fall to one side the You the bus like you are moving you feel bus is traveling at the bus goes bus isthe bus thrown backward a constant speed, pulling the other when because the around a corner. isn’t forward. us accelerating or decelerating.

What is a Carousel? • It’s an amusement ride made of a rotating platform with seats for the passengers • The seats are typically horses, but can include dogs, cats, rabbits, pigs, deer… • Animals often move mechanically up and down to simulate galloping • Music is often looped while the ride spins

Origins of the word “Carousel” • Originates from the Spanish word “carosella” which means “little war” • In the 1100’s Turkish and Arabian horsemen used carousels as an exercise to prepare for combat and as a game. • It was used to train men in cavalry because it prepared and strengthened the riders for combat.

“Flying Horses” • Early carousels didn’t have platforms, just the animals hanging from poles and chains • The animals would fly out from the centripetal force when the device began to spin • The carousels were either pulled by walking animals, people pulling ropes, or cranking

Platform • The platform carousel was developed in the mid 1800’s • The animals were attached to the wooden floor which was suspended in the air from a centerpole • Theses devices were steam-powered

1909 Illions Carousel Speed 4 Revolutions/Minute Diameter 7. 75 Meters Circumference of the outer ring of the horses Angle banking of the floor 50 Meters -4° Manufacturer M. C. Illions Direction of travel Clockwise

Questions and Calculations Where would you need to sit if you wanted to experience the greatest speed? You would want to sit on the outside because all the horses complete the circle in the same amount of time. The horses on the outside have to travel more distance in the same amount of time, which gives them a faster linear speed. Linear velocity is different between the two rows of horses while the angular velocity is the same between all the horses. If you were on a horse and were to drop a coin while the ride was in motion, where would it land relative to you? It would land behind you because of centripetal force.

Questions and Calculations Find centripetal acceleration: a. R = v 2 = (3. 33 m/s)2 = 2. 86 m/s 2 r 3. 875 m Find the frequency in Hertz: 4 rev. min = 0. 0667 Hz min 60 s Find linear velocity 50 m – 0 m 15 s – 0 s = 3. 33 m/s

Horizontal Accelerometer Vertical Direction: T = mg/cosØ Turn onto 95: 15° 90° - 15° = 75° Horizontal Direction: T = mg/sinØ mg tanØ = ma a = g tanØ a = (9. 8 m/s 2)tan(75) = 36. 57

Summary Name the ride that fits the description Kinetic energy is being converted into gravitational potential energy: Scream, they carry you up to the top, which uses kinetic energy. When you’re at the top you have gravitational potential energy. PEgrav = mgy The translational (linear) accelerations is negative: Mind Eraser, at the end of the ride you come to an abrupt stop. v 2 – v 1 = a t 2 – t 1 The centripetal acceleration is significant: Nightwing, because the ride spins in a circle really fast to make you feel like you are flying. a. R = v 2 r

Reflection • • • Had a good time Bus didn’t break down Stay at the park later Buy the flash passes Lunch buffet