work. work …is a force acting through a distance. work is only done, when a force moves an object...
TRANSCRIPT
![Page 1: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/1.jpg)
WorkWork
![Page 2: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/2.jpg)
Work…is a force acting through a
distance.Work is only done, when a force moves
an objectAnd the object must be moved in the
direction of the force
In other words... Work = Force x distance (W = Fd)
d
![Page 3: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/3.jpg)
Work cont.Is work done in the following examples...
1.You push as hard as you can against a door, but it does not move.No: there is no movement
2.You lift a basketball off the floor.Yes: there is force and distance
3.Superman stops a speeding jet.No: there is not movement in the direction of the
force
4.You put your backpack on and carry it to the door.No: the movement is not in the direction of the force
5.You hold your backpack for five minutes.No: there is no time involved in work
![Page 4: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/4.jpg)
Work cont.Work is measured
in newton-meters (Nm)
-the newton is from force
-the meter is from distance
1 Nm = 1 Joule (J)
![Page 5: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/5.jpg)
Power…is the rate at which work is done.
Power = Work TimeThe unit of power is the watt (W)1 Watt = 1 joule per second (J/s)
Electricity is measured in kilowatts (kW)
Horsepower (hp)One hp equals 750 watts
![Page 6: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/6.jpg)
Practice Problems for
Work & Power
![Page 7: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/7.jpg)
A car runs out of gas. Fortunately, there is a gas station nearby. You must exert force of 715 N on the car in order to move it. By the time you reach the station, you have done 2.72 x 104 J of work. How far have you pushed the car?
W= F=d=
What Formula do you need to use? _____________________
Solve the Problem:
![Page 8: Work. Work …is a force acting through a distance. Work is only done, when a force moves an object And the object must be moved in the direction of the](https://reader036.vdocument.in/reader036/viewer/2022071806/56649d815503460f94a665d2/html5/thumbnails/8.jpg)
The world’s most powerful tugboats, which are built in Finland, are capable of providing 8.17 x 106 W of power. How much work does one of these tugboats do in 12.0 s?
W=P=d=
What Formula do you need to use? _____________________
Solve the Problem: