newton's laws of motion -...
TRANSCRIPT
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NEWTON'S LAWS OF MOTION
Learning Targets1. I can define the net force of an object as the sum of all of the
forces acting on it.2. I can create and use force diagrams / free body diagrams to
compare the forces on an object.3. I can compare an object’s direction and speed when its net force
is zero and when its net force is greater than zero.4. I can analyze and compare forces that oppose motion of an
object.5. I can explain Newton’s Laws of Motion
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Vocabulary within this set of notes1. Inertia:
2. Mass:
3. Newton's First Law of Motion:
4. Newton's Second Law of Motion:
5. Newton's Third Law of Motion:
Newton’s Laws of Motion
Linking Forces with
Motion!
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NEWTON’S FIRST LAWA. “The Law of Inertia”
B. Inertia = resistance to change in motion
C. Larger Mass = greater inertia, or greater resistance• “An object at rest will remain at rest unless acted on by an unbalanced force. An object in
motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.”
• An object will only accelerate with an unbalanced net force. (Speed up, slow down, change direction)
A. If the net force = 0, then a=0
Objects that are not moving, do not want to move.Objects that are moving, do not want to accelerate! (They don’t want to speed up, they don’t want to slow down, they don’t want to change direction!)
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The greater the mass, the greater the inertia, the greater the resistance to
change its state of motion!
Newton’s 2nd law• Acceleration is produced when a force acts on a mass.
• The greater the mass of the object, the greater the amount of force needed to accelerate the object.
• FORCE = MASS x ACCELERATION• F= ma• Answer to example:• 50 newtons• Or 50 N
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F=MA• Smaller mass requires less force to give it the same amount of acceleration!
• Larger mass requires more force to give it the same amount of acceleration
NEWTON’S THIRD LAWA. Every action force has an equal and opposite
reaction force
B. Forces occur in pairs
C. “The Rocket Law”
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Newton’s 3rd law
• “For every action there is an equal and opposite re‐action. Forces come in pairs”
Action and Reaction Forces, • Forces always occur in pairs.
– For every action force, there is an equal and opposite reaction force.
• Forces in a force pair do not act on the same object.
• Equal forces don’t always have equal effects. – Example: The action force of Earth pulling on an object and
causing it to fall is much more obvious than the equal and opposite reaction force of the falling object pulling on Earth.
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Fluid/bottle pushes air
Air pushed fluid/bottle