DYNAMICS
Levitation Homopolar motor
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Once the magnet is set in motion, why does it stay in motion?
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Once an object is set in motion, a force is not required to keep it in motion
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III. Definition - study of relationship between force & motion
A) 3 Laws of Motion
1st Law - Law of Inertia
An object at rest...
tends to stay at rest.
(Larger) Inspired by Dr. Richard Feynman
Object in motion
tends to maintain its' speed and direction...
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"Why is it initially so difficult to pedal a bike when you start from rest?" |
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"And why is it so easy to pedal the bike once you obtain your desired speed?" |
Inertia - Object at rest tends to stay at rest (force required to change motion)
Object in motion tends to stay in motion
(force
only needed to offset friction)
..... unless acted on by an unbalanced force.
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Balanced Forces
Unbalanced Forces
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In other words ... If a moving object has no unbalanced force on it,... it would maintain its speed and direction forever! |
Unbalanced Forces
Change Motion
Speed
and/or
Direction
Moon has Unbalanced Force On It!
St. Mary's HS Physics
St. Mary's HS Physics
Larger the mass,
the greater the inertia
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Inertia and Mass Directly Related
Twice the Mass,
Twice the Inertia
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"Why are the most massive (most inertia) football players lineman?" |
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"Why are the least massive (least inertia) football players receivers?" |
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"Receivers want to change motion, lineman want to hold their ground" |
What Makes The
World Go 'Round?
Nothing!
An Object in Motion
Tends to Stay in Motion
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St. Mary's HS Physics |
St. Mary's HS Physics
| Onsite Krampf |
Go to Robert Krampf's website
Eggs and Inertia - Physics.org
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"Which cart has the greatest inertia?" |
© Tony Mangiacapre., - All Rights Reserved [Home] Established 1995 - Use any material on this site (w/ attribution)