Homework Due WednesdayIn Lab

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Homework (Due Wednesday)In Lab

• Page 66 Review Questions s 2, 4, 6-11,
  13-16, 18-20
• Do Now!!!
• How long does it take for a ball to hit the
  ground from a balcony 15m high?

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Every action has an equal and opposite reaction.
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Chapter 6.3 Action and Reaction Pairs
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Chapter 6.4 Action and Reaction on Different
Masses
Consider the recoil of a rifle
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Chapter 6.4 Action and Reaction on Different
Masses
Consider a cannon and cannon ball
The shuttle continually recoils against the
expelled gas from the rockets. No atmosphere is
needed for this interaction.
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Chapter 6.5 Do Action and Reaction Forces Cancel?
It depends on context
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Force and Friction
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Chapter 6.6 The Rickshaw Problem
Acceleration is due to net force
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Chapter 6.6 The Rickshaw Problem
Net force on the rickshaw?
Pull of man friction of wheels on ground
Net force on the man?
Push of ground on man - Pull of rickshaw on man
Net force on the ground?
Push of man on ground friction of ground on
wheels
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Chapter 6.7 Action Equals Reaction
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Consider the following three examples. The action
force is stated determine the reaction force.
Use the pop-up menu to view the answer.
              Athlete pushes bar upwards.
              Bowling ball pushes pin
rightwards.
          Compressed air pushes balloon wall
outwards.
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• Check Your Understanding1. Consider the
  interaction depicted below between foot A, ball
  B, and foot C. The three objects interact
  simultaneously (at the same time). Identify the
  two pairs of action-reaction forces. Use the
  notation "foot A", "foot C", and "ball B" in your
  statements.

• Answer
• Fa on b is equal and opposite to Fb on a
• Fc on b is equal and opposite to Fb on c

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• . Identify at least five pairs of action-reaction
  forces in the following diagram.

• F man feet on ground
• F ground on mans feet
• F mans hand on left side of rope
• F of left side of rope on mans hands
• F of monkey pulling to right on rope
• F of rope pulling left on monkey
• F of monkey pulling left on rope
• F of rope pulling right on monkey
• F of rope pulling left on tree
• F of tree pulling right on monkey

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Good Practice Problems)

• A high diver jumps off a high platform. You time
  him with your watch and it takes 2.4s for the
  diver to hit the water. A) How high is the
  platform? B) How fast is the diver going the
  instant before he hits the water?
• John stubs his toe on the coffee table with a
  force of 100N. A) What is the acceleration of
  Johns 1.80kg foot? B) What is the acceleration
  of the table if it has a mass of 20.0kg?
• What is the minimal force a mother must exert to
  lift her 5.0kg baby straight up out of its crib?
• A common malady in runners who run on too hard a
  surface is shin splints. If a runners 7kg leg
  hits the pavement so that it comes to rest with
  an acceleration of -200.00m/s2 on each hit, how
  much force must the runners leg withstand on
  each step?
• In the district soccer championship finals,
  Elizabeth kicks a 0.600kg soccer ball with a
  force of 80.0N. How much does she accelerate the
  soccer ball

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Do now!!!

• A car (5000kg) collides with a truck (10000kg)
  causing the car to slow down at a rate of 7m/s2.
  What is the acceleration of the truck?