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Chapter 2 – Lesson 2. http://ed.ted.com/lessons/joshua-manley-newton-s-3-laws-with-a-bicycle. Newton’s 1 st Law. An object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an unbalanced force. Part 1: An Object at Rest.
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Chapter 2 – Lesson 2 http://ed.ted.com/lessons/joshua-manley-newton-s-3-laws-with-a-bicycle
Newton’s 1st Law An object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an unbalanced force.
Part 1: An Object at Rest • Identify an object at rest Ex: chair on the floor, a plane on a runway • These objects will not start moving until a is exerted on them. • Ex: push or pull You tend to fall backward when your school bus starts to move.
Part 2: An Object in Motion • An object moving at a certain velocity will continue to move at the same speed and in the same direction unless some acts on it. • http://www.physicsclassroom.com/mmedia/newtlaws/il.cfm forever unbalanced force Ex: Riding in your car. When your mother or father comes to a stop then you would continue to move, however your seatbelt stops you.
Balanced Force Equal forces in opposite directions produce no motion
Unbalanced Force Unequal opposing forces produce an unbalanced force causing motion
If objects in motion tend to stay in motion, why don’t moving objects keep moving forever? • Things don’t keep moving forever because there’s almost always an acting upon them. • A book sliding across a table slows down and stops because of the force of • If you throw a ball upwards it will eventually slow down and fall because of the force of unbalanced force friction gravity
Inertia • The tendency of an object to resist a change in its motion Inertia can be described as the tendency of an object to keep doing whatever’s it’s doing.
Inertia • Inertia is the reason objects at rest and objects in motion remain at rest remain in motion Inertia is the reason you slide toward the side of a car when the driver makes a sharp turn.
MASS and INERTIA INERTIA MASS • The more an object has, the more the object has. • Therefore an object with a small mass will have a inertia • And an object with a large mass will have a inertia. • Bigger objects are to start & stop SMALL LARGE HARDER Which vehicle has more inertia?
The truck is in motion. What is the force that causes it to stop? The car is at rest. What is the force that causes it to move? Thepush of the stopped car. The push of the truck.