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Work and Power. Hello!. You Need: Pencil Science Notebook Science Folder Calculator Drawing from Fri Everything else goes into the corners of the room. Bell Work: Open your science notebook to a new page. Title the page “Work.” Answer the question below.
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Hello! • You Need: • Pencil • Science Notebook • Science Folder • Calculator • Drawing from Fri • Everything else goes into the corners of the room. Bell Work: • Open your science notebook to a new page. Title the page “Work.” Answer the question below. • As a student your teacher expect you to go home and do homework. Are you really doing work? Why or Why not?
To Do Work: You Need 2 Things • A Force – A push or a pull on something. • Push a chair • Pull your notebook off a desk. • Other examples? • Motion – Movement • Measured in miles • Kilometers • Meters • Other examples?
Force is necessary to do work. • Work: The use of force to move an object some distance. • In order for work to happen, we have to have the following: • Force • Motion • Motion in the direction of the force • If one of those three things is not present, then no work is being done.
Bell Work Answer • You are doing homework. Is there force? Is there motion? Is the movement in the direction of the force? • Discuss with a neighbor if doing your homework is actually “Work.”
Rotating Lab Stations • Label your paper 1-4, skipping two lines in between numbers. • Go to your assigned lab station. You need your notebook and a pencil. • With your group, decide if the picture on your station is doing work. • If it is doing work explain, why? If it is not doing work, explain what characteristic is missing. • You will be moving around to all 4 lab tables.
Number 1 – Picking a chair up and walking forward Force Motion
Number 3 – Picking a weight up above your head Force Motion
Number 4 – Pushing a lawnmower. Force Motion
Calculating Work • Work is a measure of how much force is applied over a certain distance. • The formula for finding the amount of work done is below: W= Force x Distance W=FxD
Other Equations Work = Force x Distance Force = Work / Distance Distance = Work / Force W F D
Units • The formula for work is W=FxD
Calculations Practice • W? • F = 10 N • D = 5 M • W=FxD • W= 10N x 5M • W= 10 x 5 • W= 50 J
Calculations Practice • W? • F = 12N • D = 9M • W=FxD • W=12N x 9M • W= 12 x 9 • W= 108 J
Calculations Practice • W18 J • F = ? • D = 3M • Force = Work/Distance • Force = 18 J / 3 M • F= 18/3 • F= 6N
Review • A body builder lifts 350 pounds above his head. Is any work done? • A. Yes • B. No
Review • A body builder lifts 350 pounds above his head. Is any work done? • A. Yes
Review • A scientist delivers a speech to an audience of his peers. Is work done? • A. Yes • B. No
Review • A scientist delivers a speech to an audience of his peers. Is work done? • B. No
Review • If a man pushes a concrete block 10 meters with a force of 20 N, how much work has he done? • A. 200 N • B. 150 J • C. 200 J • D. 150 N
Review • If a man pushes a concrete block 10 meters with a force of 20 N, how much work has he done? • C. 200 J