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51 Cards in this Set
- Front
- Back
Fulcrum |
The pivot point on the lever that doesnt move move |
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Effort Force |
A push or pull on one end of the lever |
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Load |
The object that is lifted with support of the lever & effort force |
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Load arm |
In a lever the distance from the load to the fulcrum |
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The clasd that a lever belongs to depends on the position of the ______ |
Effort force |
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What advantage does >1 give? |
Force advantage |
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What advantage does =1 give? |
Change of direction |
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What advantage does <1 give? |
Speed & distance |
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What does it mean to peform work on an object? |
Exert a force on an object & move that object some distance in the direction of the force , you do work on the object. |
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Formula for work & what unit is it measure? |
Force × Distance Jules |
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Define Inclined Plane |
Ramp or slop that reduces the force you need to exert to lift something |
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The work that you do on a machine is called: |
Input work |
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work that the machine does on the load is called |
Output work |
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A machine never does more work on the load than you do on the machine. So why do machines make work easier? |
It changes the size of direction of the force |
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Mechanical Advantage |
The comparison of the force produced by a machine to the force applied to the (ratio) machine |
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Formula for MA & units used? |
FLoad force ÷ FEffort force No units are used |
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Example: If the MA is 6 how much easier would it be? |
6x easier |
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(For levers) what's the formula for MA? |
MA= Effort arm ÷ Load arm |
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Winch |
Consists of a small cylinder & crank or handle. |
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Label the winch |
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Wheel & Axle |
Two turning objects that are attached together |
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Gear |
Rotating wheel-like object with teeth around its rim |
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Gear train |
Group of two or more gears |
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Driving gear |
Drives the other gear , may turn cause of turning handle or motor |
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Driven gear |
Follower , driven by the driver gear |
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Sprocket |
A gear with teeth that fit into links of a chain |
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Speed ratio formula |
Speed ratio= Number if driver gear teeth ÷ Number of follower gear teeth |
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Pulley |
A grooved wheel with a rope or a chain running along the groove. |
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Fixed pulley |
Attached to something that doesnt move |
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Movable pulley |
Attached to something else , often around the pulley itself |
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Block & tackle |
Combination of fixed & movable pulleys |
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Compund pulley |
Made up of several pulleys working together |
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Kinetic energy |
Energy of motion |
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Potential energy |
Stored energy |
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Types of Potential energy |
-Chemical -Gravitational -Elastic |
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Transmission |
Energy is transferred from one place to another |
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Efficiency |
How much of the energy you gave to the machine was transferred to the load by the machine |
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Efficiency formula |
Efficiency= work done by lever on load ÷ work done on lever effort force |
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Why is the efficiency always lower that 100%? |
Work done on a machine= work done by machine + energy lost as heat due to friction |
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Pressure formula |
Pressure= Force ÷ area or p= f ÷ a
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What is pressure measured in? |
Pascal (Pa) Kilopascal (kPa) kPa=1000 Pa |
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When decreases force weight |
When the weight is spread over a larger area |
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Pascals Law |
States that pressure exerted on a contained fluid is transmitted along the sides of the container. |
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Hydraulic lift |
Is a mechanical system that raises heavy objects |
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Closed system |
Self contained collection of parts |
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Hydraulic systems |
Use the force of a liquid in a confined space, such as an oil pipeline |
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Pneumatic system |
Seals air in a mechanical system. |
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Pneumatic examples |
-Jackhammer -high-speed drill -Staple guns -pneumatic nailers -Sandblasters |
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Hydraulic systems |
Heavy equipment operator bi-directional tractor Backhoe |
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Valve |
Used to control the fluid |
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Pumps |
Use Automatic valves |