How does a simple machine make a job easier?
By applying a force
What are the six main types of simple machines?
Wheel and axle, pulley, inclined plane, screw, wedge, lever
What is a Rube-Goldberg machine?
- Purposely over-engineered
- Complete a simple task in a complicated fashion
- Includes a chain reaction
- Multiple simple machines
How many energy transfers and transformations take place within a machine?
- Kinetic energy
- Potential gravitational energy
What is the difference between the effort and load force?
- A load is what we add
- An effort is what we put in
Work in is equal to…
Work out
Whats the difference between force multipliers, speed multipliers and direction changers?
- Force multiplier: Changes the size of the force
- Speed multiplier: Makes things speed up
- Direction changers: Changes the direction of the force
What are the 3 classes of levers and their applications?
First class lever – L,F,E
Second class lever – F,L,E
Third class lever – F,E,L
What’s the mechanical advantage of levers?
The ratio of output force to input force.
Whats the difference between a simple and multiple pulley systems?
- Simple pulley system: It doesn’t reduce the amount of force, but it does change the direction required to move the load.
- Multiple pulley system: A compound system, reduces the amount of force required to move an object.
Whats the MA (Mechanical Advantage) for pulleys?
It’s equal to the number of ropes supporting the movable load.
How do you calculate effort and force load for pulleys?
It’s done by dividing the load by the number of ropes.
What are gears?
Toothed wheels that mesh with other gears
Gears can be…
Force or speed multipliers, and/or direction changers.
What are driver gears?
The gear that transmits the rotational motion of a motor or other device through the drive shaft
What is the driven gear?
The receiving gear
What is the idler gear?
The gear placed between the input and output shafts
What’s the use of a bevel gear?
Transmits power to two axles spinning at different speeds
What’s the rack gear and pinion gear?
- Rack gear: Convert rotating movement into linear motion.
- Pinion gear: The smaller of two meshed gears in an assembly
Whats the mechanical advantage of gear trains and also gear ratios?
The ratio of output force to input force in a system
Whats the MA of an inclined plane?
The length divided by the height
How do you calculate the MA of a gear
Driven / driver
How do you calculate the ratio of a gear
Driver / driven
What is effort force, force load and effort distance?
- Effort force: Effort put in
- Force load: Requires effort force
- Effort distance: The distance from the effort on a lever to the fulcrum
