Simple Machines 1
Machines with many parts are called
Complex machines
Another word for force
Effort
Give an example of a screw that you can find around your house
lightbulb, screw, bottle cap
An inclined plane with a long surface will have a ________ angle of incline?
The job will be _____________.
small
easier
Name 3 examples of a wedge
teeth, nails, claws, knife, doorstop
Machines with a few parts are called
simple machines
Give an example of a second class lever
Examples: Sweeping using a broom; standing on tip toes; flexing elbow or knee joints, etc.
How do wheels and axles make work easier?
They help transport heavy objects.
An inclined plane with a short surface will have a _______ angle of incline.
The job will be _______.
big
harder
There is a myth that Egyptians used what to help build the pyramids?
Rollers
What are the basic simple machines
Pulleys, levers, wedges, inclined planes, wheel and axle and screws
When are levers most often used
To lift and move loads
Describe each lever class and what makes them differen
Class 1 - the fulcrum is in the middle
Class 2 - the load is in the middle
Class 3 - the effort is in the middle
What does work mean?
it is done when an applied force causes an object to move in the direction of the force
What's the relationship between force and friction?
Friction slows down the pushing force on an object
Why are simple machines important?
They make work easier
How does the size of the wheel affect the speed at which an axle turns?
A larger wheel will make the axle turn more slowly
Explain how a wheel and axle help you move heavy objects
By distributing the weight of the object over a larger area.
Pulleys make it possible to _______ and _________ loads.
raise
lower
Give an example of a pulley in real life.
The point on a lever that does not move
Fulcrum
Provide two examples of an inclined plane.
Examples: slide on playground; handicapped ramp; a ladder; a roller coaster ride (track).
Describe how the position of the fulcrum affects the effort needed to lift an object with a lever
The closer the object is to the fulcrum, the less effort is needed.
What happens when 2 or more pulleys are used together?
It increases the force to make it 2 times easier.
A screw is a tool that ________ things together.
holds