work and power. hello! you need: you need: pencil pencil science notebook science notebook science...
TRANSCRIPT
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.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 chairPull your
notebook off a desk.
Other examples?
Motion – Movement
Measured in miles
KilometersMetersOther
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 2 – Mr. Feeny at his office
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
W
FD
Work = Force x Distance
Force = Work / Distance
Distance = Work / Force
Units
The formula for work is W=FxD
What is being measured?
Unit
Force Newton (N)
Distance Meter (M)
Work Newton x Meter or Joule (J)
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. YesB. 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. YesB. 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