Upload
sibyl-todd
View
224
Download
3
Tags:
Embed Size (px)
Citation preview
Work
Lifting books out of your backpack? Carrying your backpack to class?
Pushing a car that is stuck in the snow?
Rolling a bowling ball?
What is Work?
Is this cat doing work?
Work is done on an object when the object moves in the same direction in which the force is exerted.
What is Work?
Sometimes force is applied to an object, but no work is
done.
If you push on a block and it doesn’t move, you have not
done ANY work in the scientific sense.
Which force is most likely to do
work on the block?
Work is done by forces over a distance. Work is done on objects. When force is measured in newtons and
distance in meters the SI unit for work is the newton*meter
A newton*meter is called a Joule
Calculating Work
To calculate work, you multiply the force by the distance the object moves in the direction of the force.
Calculating Work
How much work is done if the block is raised 3 meters?
Force (F)= 50 N distance (d)= 0.5 m
How much work is done on a 10-newton block that is lifted 5 meters off the ground by a pulley?
Practice Time!