Pseudo-Forces

# Pseudo-Forces

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## Pseudo-Forces

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##### Presentation Transcript

1. Pseudo-Forces

2. What in the world is it? Let’s Bing it: • http://www.bing.com/search?q=Pseudo+Forces&src=IE-SearchBox&Form=IE8SRC&adlt=strict • Here’s a good result from • http://www.answers.com/topic/fictitious-force

3. Here’s a good result from • http://www.answers.com/topic/fictitious-force • Noun. The physically apparent but nonexistent force needed by an observer in a noninertial frame to make Newton's laws of motion hold true. Also called fictitious force. • The force F does not arise from any physical interaction but rather from the acceleration a of the non-inertial reference frame itself.

4. Quote Continued: A fictitious force arises when a frame of reference is accelerating compared to a non-accelerating frame. As a frame can accelerate in any arbitrary way, so can fictitious forces be as arbitrary (but only in direct response to the acceleration of the frame). However, four fictitious forces are defined for frames accelerated in commonly occurring ways: one caused by any relative acceleration of the origin in a straight line (rectilinear acceleration),[8] two caused by any rotation (centrifugal force and Coriolis force) and a fourth, called the Euler force, caused by a variable rate of rotation, should that occur.

5. Remember these words • Inertial Frame of reference- • Frame of reference that is not accelerating. • Law of inertia holds. All accelerations are caused by forces. • Newton’s 3 laws apply. • Non-inertial Frame of reference- • Frame of reference has some acceleration • Objects seem to break law of inertia and accelerate in strange ways. They can move without forces. • Newton’s 3 laws may or may not apply. • i.e., weird things appear to happen.

6. Psuedo-Forces • In an elevator accelerating upwards you will feel heavier, like you have more mass. • In an elevator accelerating downwards you will feel lighter, like you have less mass. • At Worlds of Fun on the Finnish Fling, the spinning barrel ride, gravity appears to go sideways. Also the Detonator. • If you slam on the brakes, loose objects in you car will seem to accelerate forwards.

7. Centrifugal Force • In a rotating frame of reference, it looks like there is a force pushing away from the center of the circle. • Really, bodiestry to move instraight line.Walls push inward to makecircular motion.

8. Next subtopic. • Debate: Someone on the equator, 3000 miles south of KC, launches an unguided rocket due North and it goes 3000 miles. Will it hit KC?

9. Coriolis Force • Objects moving in a straight line on a rotating surface (like the globe) seem to be deflected from the frame of reference of the rotation. • If I fire a projectile far enough, the world will rotate a little bit before it hits the ground, causing my calculations to be a little bit off.

10. Definition:http://youtu.be/BPNLZyBNPTE • When you shoot a basket, where do you aim with the basket ball? http://youtu.be/7TjOy56-x8Q • Ball bearing http://youtu.be/Wda7azMvabE • Merry Go Round http://youtu.be/_36MiCUS1ro • Earth at Equator http://www.youtube.com/watch?NR=1&v=Pb69HENUZs8&feature=fvwp&safety_mode=true&persist_safety_mode=1&safe=active • Force arrows:http://youtu.be/49JwbrXcPjc • Toilet Flushing south of equator. http://www.youtube.com/watch?v=hPz3ONsRuc0 • Water, Balance egg, and walking on the equator. http://www.youtube.com/watch?v=ZBVntSA-qoQ&feature=related