Chapter 2: Forces Section 1: The Nature of Force

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Chapter 2 Forces Section 1 The Nature of Force

• How many different ways can you move the book on
  your table? Try it!

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The Nature of Force

• Write down all the different ways you either made
  the book move or thought of making the book move.
• What did all the different ways have in common?
• Did the book move when there was no push or pull?
• What do you think is the scientific definition of
  force?

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Unbalanced Forces

• Why is the first black arrow so large?
• Unbalanced forces can cause objects to
  ____________________ ______________________.

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Balanced Forces

• Balanced forces are _______ _____________________
  ____.
• Do they change the objects motion?

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Drawing Force Arrows

• Does it matter how long the arrows are?
• What does a long arrow mean?
• What does a short arrow mean?
• What does magnitude mean?
• Does it matter what direction the arrows are
  pointing in?
• Draw a quick diagram that shows the forces acting
  on a soccer ball being kicked.

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Drawing Force Arrows
Big Kick
Light Kick
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Newtons First Law of Motion

• When a car suddenly stops, why does your body
  keep moving forward?
• Will a pen on a desk move if it is left alone?
• Inertia is the ________________
  __________________________________________________
  ___.

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Newtons First Law of Motion

• An object at rest will remain at rest, and an
  object that is moving at a constant velocity will
  continue moving at a constant velocity, unless
  acted upon by an unbalanced force.

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Newtons First Law of Motion

• Why is Newtons First Law of Motion also called
  the Law of Inertia?

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Mass

• Mass is the _______________ ______________________
  __.
• The SI unit for mass is_________.
• The greater the mass of an object the greater its
  ________.
• Give an example of the above.

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Mass and Inertia

• Imagine youre riding in a car with your 2 year
  old sister. The car suddenly stops as your mom
  hits the breaks to avoid an accident. Who will
  fly forward and hit their seatbelt harder? Why?

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Directions
5 pts

• Draw 2 tug-of war scenarios where A) one side
  wins, and B) no side wins. Include arrows that
  represent the direction and magnitude of the
  forces present. The arrows should be longer if
  the force is more and shorter if the force is
  less! Be Creative!!

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Directions

• You have 20 Minutes to Complete a Double Bubble
  map comparing Unbalanced Forces and Balanced
  Forces.

Worth 5 points if complete and stapled to your
warm-up
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Directions
5 pts

• Choose 3 Photographs from section 1 in Chapter 2
  (pg. 36-41) and write Descriptive Captions about
  them. Use key terms and write at least 2
  sentences about each photo! Think about what
  direction the forces are going and if the forces
  are balanced or not.

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Concept Map Word Bank
5 pts

• objects at rest
• objects in motion
• net force
• at rest
• in motion
• inertia
• an unbalanced force acts on them
• unbalanced forces
• balanced forces
• net force of zero

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Directions

• You have 20 Minutes to Complete the Summary
  Assignment and will receive 2 stamps (10 points)
  when you have 17 sentences. Write one sentence
  for each paragraph in your own words in your book
  from pages 36-41.