Work and Machines Flashcards
What is needed for work to be done
Distance
Work is measured in what
Joules
SI unit of power
Watt
Why do we machines
Machines make it easier to do work
What is it called when you use a machine
Mechanical Advantage
If you increase distance what else do you increase
You increase Advantage
IMA means
The ideal mechanical advantage
AMA means
Actual mechanical advantage
IMA is always greater than what
AMA
A simple machine that consists of a rigid bar that turns on a pivot point
Lever
A force that tends to cause q rotation about a pivot point
Torque
A system is in rotational equilibrium when the sum of torques on the system is zero
Law of Torques
In the 1st class lever what os in the middle
The fulcrum
In the 2nd class lever what is in the middle
The output force
In the 3rd class lever what is in the middle
The input force
A simple machine consisting of a wheel with a rod running through its axis that acts as the pivot point
Wheel and Axle
A wheel and azle is a modification of what
A lever
A simple machine that consists of a wheel with teeth
Gear
A simple machine that consists of a wheel and axle system with a Groove around the perimeter of the wheel in which a rope belt or cable moves with the wheel as it rotates
Pulley Systems
IMA = 1
Single fixed pulley
IMA = 2
Single moveable pulley
IMA = number of rope segments (4)
Block and Tackle
Additional pulleys mean
Additional friction
More friction means less what
Less efficiency
A simple machine that consists of a plane whose opposite ends are at different heights
Inclined Plane
What kind of inclined planes have a higher mechanical advantage
Shallower
Mechanical advantage depends on what
Steepness
A simple machine consisting of two inclined planes attached at an acute and used to separate a material apart
Wedge
What are two examples of inclined planes
A wedge and a screw
A simple machine that consists of an inclined plane wrapped around a cone or a cylinder in a spiral pattern
Screw
In a screw where does the mechanical advantage come from
It’s threads
The steeper the thread the __?__ mechanical advantage you gain
Less
A machine that combines 2 or more simple machines
Compound machine
Example of a 1st class lever
Seesaw
