1.1.1b Inclined Plane, Wedge, and Screw
What are the 4 properties of a screw?
- Change rotary motion into linear motion - Used as a threaded fastener - Large MA - Large amount of friction loss
What 2 ratios define Mechanical Advantage?
- Ratio of the magnitude of the resistance and effort forces - Ratio of distance traveled by the effort and the resistance force
Interpret the following information: "3/4 8NC"?
3/4: Diameter 8: Threads per inch NC: Thread description coarse or fine
What is a Inclined Plane able to do?
Able to lift objects by pushing or pulling the load
What do the calculated ratios allow (4 things)?
Calculated ratios allow designers to manipulate speed, distance, force, and function
What is used for Effort Distance in a screw?
DE = One rotation of the effort arm (Circumference)
How is Screw defined/described?
Defined: An inclined plane wrapped around a cylinder, forming the path and pitch Described: A wheel and axle used to create rotary motion
Define pitch. How is it relate to the Resistance Distance?
Distance between threads and linear distance traveled by 1 rotation of the screw - dR: Linear distance traveled during one rotation of the effort arm = Pitch
What is a wedge?
Functions as a moving inclined plane
Define, both in words and formula, IMA.
Ratio of distance traveled by effort and resistance force Formula:
Define, both in words and formula, AMA?
Ratio of force magnitudes Formula:
What is a compund machine?
Simple machines working in combination to complete a task
What is the use of a wedge?
Tapers to a thin edge and is used for splitting, raising heavy bodies, or for tightening by being driven into something
How is the MA of a compound machine calculated?
The ratio of the output force exerted by the last machine in the series divided by the input force applied to the first machine.
Define the following symbols: dE, dR, FE, FR
dE: Distance traveled by effort force dR: Distance traveled by resistance force FE: Magnitude of effort force FR: Magnitude of resistance force
