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Welcome back minions!!!. Warm up on board… Place work at corner of desk up front. Warm-up. Work A to Z Name 26 words associated with work… …Each word starts with a letter of the alphabet! You have 4 minutes!... Go!!!! . Work!!!. Definition of work…
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Welcome back minions!!! Warm up on board… Place work at corner of desk up front.
Warm-up Work A to Z Name 26 words associated with work… …Each word starts with a letter of the alphabet! You have 4 minutes!... Go!!!!
Work!!! • Definition of work… • Force exerted on an object that causes it to move! • So out of the examples in the warm-up, which were actually work?
Work!!! • Examples of work!
Work!!! • Has to move in the direction of the force. • Has to move a distance. • No distance = no work • No matter how much force you apply!!!
“Work” or “No Work” • 1) Work • 2) No Work
“Work” or “No Work” • 1) Work • 2) No Work
“Work” or “No Work” • 1) Work • 2) No Work
“Work” or “No Work” • 1) Work • 2) No Work
“Work” or “No Work” • 1) Work • 2) No Work
Calculating work… • Which requires more work? • Move 100 Newton object 10 meters? • Move 10 Newton object 100 meters? • Move a 5 Newton object 200 meters? • Work is calculated by: Work = Force x Distance
SI unit for work… • Mid 1800’s • Physicist • James Prescott Joule • Work is Newtons x Meters = Joule (J) • Exert 1 Newton of force to move an object 1 Meter of distance = 1 Joule
Give it a try… • 50N x 5m = 250 J • 10N x 2.5m = 25J • 100N x 300m = 30,000J
Time? • Is there a difference in work if you carry a backpack up the stairs by walking as compared to running? No! Work = Force x Distance (The rate at which work is done isn’t measured!)
We need more… • What do you think of when you hear the term “Power”? • If we factor in time with work… we are talking about POWER!!! • Power – The rate at which work is done. • It equals the amount of work done on an object in a unit of time.
SI unit for Power… • Work measured in Joules • Time in seconds • Joules per second • Watt (W) • (This is used for smaller measurements) • Kilowatt • 1000 watts • Fact: “Horsepower” • 1 Horsepower = 746 watts
How can we figure this out? If Work = Force x Distance
Calculating power… • Figure this out…
Step by step… • Power = • Power = • Power = • Power = 2,200 J/s or 2,200 W
Questions • What is work? • 1) Rate a force is used to move an object • 2) Meters per second • 3) Exert a force on an object to move it a distance. • 4) Kilogram per cubic centimeter
Questions • What is the SI unit for work? • 1) Horsepower • 2) Joule • 3) Watt • 4) Meter
Questions • Equation for work • 1) Work = Force x Time • 2) • 3) Work = Time x Distance • 4) Work = Force x Distance
Questions • What is power? • 1) Rate at which work is done • 2) Distance at which work is done • 3) Temperature at which work is done • 4) Potato
Questions • Equation for Power • 1) • 2) • 3) Both 1 and 2 • 4) None of the above
SI unit for Power • 1) Meter • 2) Horsepower • 3) Joule • 4) Watt
Homework!!! • Choose 5 activities at home that would be considered “work. • Tell me individually why each is considered “work”.