D: Mechanical Systems, section 1 and 2: machines, work, hydraulics Flashcards
What is an Archimedes screw?
A device that can pump fluids upward
What is a simple machine?
A tool or device made up of one basic machine
What are the six basic machines?
Lever Inclined plane Wedge Screw Pulley Wheel and axel
Explain a lever
A ridged bar or plank that can rotate around a fixed point
What are the advantages of a lever?
With a lever you can move a larger load than without using it
What are the disadvantages of a lever?
You have to move a greater distance than the load does for this to work
What is an inclined plane?
A flat surface at an angle to another flat surface
What are the disadvantages of an inclined plane?
- You have to exert force over a longer distance compared to lifting straight up
- generally used for small inclines
What we advantages to an inclined plane?
It makes it possible to to lift heavy objects using small force
What is a wedge?
A simple machine that looks like an inclined plane but it forced into an object
What are the advantages to an inclined plane?
It increases the force you apply to an object
What are the disadvantages to a wedge?
A wedge can only be used in one direction
What is a screw?
A cylinder with a groove cut in a spiral in the outside
What are the advantages of a screw?
It helps increase the force you use. It can penetrate materials using relatively small force it can also convert turning motion into straight
What are the disadvantages of screws?
Most will move objects very slowly
What is a pulley?
A pulley consist of a wire, rope, or cable moving on a grooved wheel
What are the advantages of a pulley?
They can be linked together and they help you lift larger loads
What are the disadvantages to a pulley?
A pulley requires a long durable rope
What is a wheel and axel?
It is a combination of two wheels of different diameters. A longer motion on the wheel creates shorter but more powerful motion at the axel
What does The acronym ‘EFL the ELF FEL’ mean?
EFL-Effort Fulcrum Load
ELF-Effort Load Fulcrum
FEL-Fulcrum Effort Load
What is a machine?
A tool that helps humans do work
What is a hydraulic system?
It uses a liquid under pressure to move loads
Finish the sentence: To increase the force of the output piston…
the input piston had to move a greater distance
What is a complex machine?
A system in which all simple machines work together
What is each part in a complex machine called?
A subsystem
What are subsystems?
They are parts that perform specific functions such as breaking or steering
What is a linkage?
A belt or chain used to transfer energy from an energy source
What is a transmission?
A special type of linkage for transferring the energy from the engine to the wheels in large vehicles
What are gears?
A pair of wheels that have teeth that interlink
Which gear is the driving gear?
The gear that has force applied to it from the outside
What is the driven gear?
The gear that the driving gear applies force to
What is mechanical advantage?
It is the amount which the machine can multiply force
What is input force?
The force applied to the machine
What is output force?
The force the machine applies to an object
What is speed ratio?
A measure of how the speed of an object is affected by a machine
What is friction?
A force that opposes motion
What is efficiency?
A measurement of how well a machine or device uses energy
