Bell Ringer 1/9/14

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Bell Ringer 1/9/14

• Use the diagram of a race track below, describe
  the 3 ways a race car would be accelerating. Use
  the letters to help describe the motion.

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MYP Unit Question AOI

• Learner Profile Word Inquirer, Thinkers,
  Communicator
• Essential Question What are simple machines and
  how do they make work (any my life) easier?
• StandardS8P3. Students will investigate
  relationship between force, mass, and the motion
  of objects.
• c. Demonstrate the effect of simple machines
  (lever, incline plane, pulley, wedge, screw, and
  wheel and axel) on work.
• Learning Target Today I am learning how simple
  machines allow me to do work easier.
• Homework Study for a quick quiz on Tomorrow ?

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Agenda

• Opening
• Lifting A rock Probe
• Work Session
• Simple Machine Notes
• Closing
• Neo K-12

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What is work?

• In science, the word work has a different meaning
  than you may be familiar with.
• The scientific definition of work is using a
  force to move an object a distance (when both the
  force and the motion of the object are in the
  same direction.)

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• Work is done on an object if two things happen
• (1) the object moves as a force is applied
• (2) the direction of the objects motion is the
  same as the direction of the force.

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• Work is measured in Joules.
• Formula W F x d or Work Force times
  distance
• Example 1 Using a 10 N force, you push a
  shopping cart 8 m. How much work do you do?

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Power How Fast Work Is Done

• Like the term work, the term power is used a lot
  in everyday language but has a very specific
  meaning in science.
• Power is the rate at which energy is transferred.

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• Power is measured in WATTS (W).

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Machines

• A machine is a device that makes work easier by
  changing the size or direction of the force.
• In general, machines allow you to overcome
• 1) gravity
• and/or
• 2) friction
• in order to move something!

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What is a Simple Machine?

• A simple machine has few or no moving parts.
• Simple machines make work easier

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How does this work?????

• Through different forces.
• Input - The work that you do on a machine
• Output- The work done by the machine on an
  object.
• The machine applies a
• force, called the output
• force, through a distance.

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Wheels and Axles

• The axle is a rod that goes through the wheel
  which allows the wheel to turn
• Gears are a form of wheels and axles

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Pulleys

• A pulley is a grooved wheel with a rope or chain
  running along the groove.
• Pulleys can be used to lift heavy objects by
  changing the direction or amount of the force.

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Inclined Planes

• An inclined plane is a flat surface that is
  higher on one end
• Inclined planes make the work of moving things
  easier

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Wedges

• Two inclined planes joined back to back.
• Wedges are used to split things.

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Screws

• A screw is an inclined plane wrapped around a
  shaft or cylinder.
• The inclined plane allows the screw to move
  itself when rotated.

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Levers

• A lever is a stiff bar that moves about a fixed
  point (fulcrum).
• A lever is used to push, poll, or lift things.
• There are three types of levers.

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Simple Machines

• Simple Machines can be put together in different
  ways to make complex machinery