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Warm Up SET UP YOUR ALBERT III What is the difference between an atom and a molecule? There is no difference An atom is composed of multiple molecules A molecule is composed of multiple atoms An atom does not exist in the natural world and a molecule does. Tuesday January 10, 2012.
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Warm Up SET UP YOUR ALBERT III What is the difference between an atom and a molecule? There is no difference An atom is composed of multiple molecules A molecule is composed of multiple atoms An atom does not exist in the natural world and a molecule does Tuesday January 10, 2012 Classwork: Set up your Albert III #3 Work & Power Notes #4 Work It!! Mini Lab Homework: Make sure you have an Albert III Complete #4
Volunteer…… Carrying books across a room is not work! WHAT IS WORK!! • Work is done when the force causes the object to move in the direction of the force. • Force does not always cause work to be done • When you push a stalled car, but it does not move…. You applied a force but did no work • 2 things must happen for Work to occur • The object moves because of a force • The object moves in the direction of the force
Calculation Work & Power • Work = F ● d • Cory lifts a 10 N box 3 m to set it on his dresser, how much work did he do? • Power- how quickly work is done • P = wunits for power are joules/ second or watt t • It takes Cory 2 seconds to complete the task, how much power did Cory use?
Mr Hale has more power than I, Ms Stein does, because he is more manly and nature bestows more power to manly men.
#4 Work It MINI LAB • Complete the mini lab with 1 partner • You may need to finish the conclusion questions for homework
Warm Up Why is work not always done when a force is applied? Whenever there is a force there is work Because the force must cause motion in the same direction for it to be work Because the force must be a pull in order for there to be work Because the force must cause motion in the opposite direction for it to be work Wednesday January 11, 2012 Classwork: #5 Simple Machines Intro #6 Brainstorm About simple machines Homework: Complete # 6
What are Simple Machines • A machine is a device that makes work easier by creating mechanical advantage • Work input is the force applied to the machine • Work output is the work the machine applies to the object • Work output is always slightly less than work input due to friction • Machines do not decrease the amount of work done!!!
Machines make work easier by changing either the force or the direction • EX OF CHANGING DIRECTION OF FORCE – see saw. Input force is down output force is up • EX OF CHANGING AMOUNT OF FORCE – inclined plane uses less force then when you lift it, but you apply the force over a greater distance Input force Output force Smaller force over longer distance
Wheel & Axle – simple machine consisting of 2 circular objects of different size • Applying a force over a greater distance to the wheel increases force on the axle • Inclined Plane- a slanted surface. A ramp • You use less force but over a larger distance • The more shallow the ramp the greater mechanical advantage • Screw – an inclined plane wrapped around itself • The more shallow the inclined plane the greater mechanical advantage the screw has
#6 brainstorm about simple machines • With your group create a list of wheel and axle, inclined plane, and screw found in daily life • You must have at least 5. Draw a diagram and describe how the mechanical advantage is created
Warm Up Log On Go to Ms Stein’s blog Click on the ASPIRE Inquiry Activity link Thursday January 12, 2012 Classwork: #7 ASPIRE Inquiry Wedges #8 ASPIRE Inquiry Levers Homework: None
Warm Up Which of the following is a correct statement concerning a wedge? A short axe blade will require less force to split wood A long axe blade will require less force to split wood There is no relationship between the length of an axe blade and force A shorter axe handle will require less force to split wood Friday January 13, 2012 Classwork: #9 Lever Lover #10 Lever LovinList Homework: None
#9 Lever Lover! Read pgs 222 – 223 and answer the questions about levers • Define lever • What are the 3 parts of every lever? • Where are the 3 parts of a lever located in a First-Class lever? Draw a diagram • Where are the 3 parts of a lever located in a Second-Class Lever? Draw a diagram • Where are the 3 parts of a lever located in a Third-Class Lever? Draw a diagram
#10 Lever Lovin Practice • On each Lever-Lovin card identify the location of the force, load, and fulcrum • Separate each type of lever into first, second or third-class levers. • Copy the chart you create on #10 • Diagram 1 example of each class lever