Chapter 16- Machines Flashcards
What unit is work measured in?
A joule (J)
What is the formula for work?
Work= force x distance
What is any device that helps people do work?
Machine
What is a tool made up of one or two parts?
Simple machine
What contains one or more simple machines among its parts?
Compound machine
How do machines make work easier?
Machines make work easier by either decreasing the force required to do a task or they apply the force over a longer distance.
How does friction affect the work of a machine?
Friction uses lubricants.
What is the support of a lever called?
Fulcrum
What is the force of an object on a lever?
Load
What is a force applied to the end of a lever to lift a load?
Effort force
How do first-class, second-class, and third-class levers differ?
They differ because of the location of the effort force, fulcrum, and load.
What are the 6 types of simple machines?
- Inclined plane
- Wedge
- Screw
- Wheel and axle
- Pulley
- Lever
How are a wedge and screw related to an inclined plane?
A wedge is 2 inclined planes put together and a screw is an inclined plane wrapped in a spiral.
What types of simple machines are used in an escalator?
Wheel and axle, wedge, pulley, and inclined plane.
How are the fulcrum, effort force, and load related?
They are all parts of a lever and can always be in different positions.
How is a screw like an inclined plane?
A screw is an inclined plane wrapped in a spiral.
How much work is done when a 5N force moves a load 2m?
10 J
What simple machine do you use when you twist the lid of a pickle jar?
Screw
What is a block and tackle made from?
A series of pulleys
What kind of lever has the fulcrum in the middle?
First- class
What kind of lever has load in the middle?
Second-class
What kind of lever has the fulcrum at one end, load on the other, and effort force in the middle?
Third-class
