Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
54 Cards in this Set
- Front
- Back
When you exert a FORCE ON AN OBJECT that causes it to move, it is called ?
|
WORK
|
|
There is no work without ____?
|
motion
|
|
Work = _____x _____
|
force
distance |
|
A Joule= what?
|
one newton meter
|
|
A unit of work is what?
|
the amount of work you do when exert a force of 1 Newton to move an object a distance of 1 meter
|
|
The force required to accelerate 1kilogram of mass at 1 meter per second is called ?
|
Newton or a UNIT OF FORCE
|
|
A device with which you can do work in a way that is easier or more effective is called what?
|
A MACHINE
|
|
How does a machine make work easier?
|
By changing the amount of roce you exert and the distance or direction in you exert force
|
|
The force you apply to the machine is called?
|
INPUT OR EFFORT FORCE
|
|
The force applied by the machine is called?
|
OUTPUT FORCE OR RESISTANCE FORCE
|
|
For tools to be a machine it must do one of more of what 3 things?
|
1.multiplying force - output must be greater than input force. (ex: a lever, inclined plane)
2.multiplying distance- allows you exert force over shorter distance. (ex:hocky stick,rake,) 3. change directions-just change the direction of the force |
|
The number of times a force applied to a machine is MULTIPLIED BY THE MACHINE is called?
|
mechanical advantage
|
|
What is the formula for mechanical advantage?
|
MECHANICAL ADVANTAGE=OUTPUT/INPUT
|
|
When the mechanical advantage is greater than 1 what happens?
|
More force comes out of the machine than is put into the machine
|
|
What is the Mechanical Advantage of changing direction?
|
Input and output are same
Mechanical advantage is 1 Force in different direction |
|
Efficiency of Machines staes that what happens?
|
1. Output work is less
2. Input work is more 3. compared they equal a percentage |
|
Formula for calculating Efficiency is what?
|
Output divided by input work x 100 % = efficiency
|
|
What is actual mechanical advantage?
|
the mechanical advantage of a machine is a REAL LIFE SITUATION
|
|
What is ideal mechanical advantage?
|
the advange of a machine without FRICTION. input and output are equal= 100%
|
|
A simple machine that is flat, with slanted surface is?
|
Inclined plane
|
|
You exert force with an inclined plane over a ______ distance?
|
longer
|
|
What is the advantage formula of an incline plane?
|
length of incline divided by height of incline
|
|
The efficiency of an inclined plane is conncected to work lost due to ______?
|
friction
|
|
What is a device that is thick at one end and tapers to a thin edge at the other end?
|
WEDGE
|
|
What is an inclined plane wrapped around a cylinder?
|
screws
|
|
What are ridgid bars that are free to pivot, rotate about a fixed point?
|
LEVERS
|
|
What is the fixed point on a lever which ALLOWS IT TO pivot?
|
FULCRUM
|
|
How do you calculate the ideal mechanical advantage of a lever using the distances between the forces and the fulcrum.
|
DISTANCE from fulcrum to input force DIVIDED BY distance from fulcrum to output force.
|
|
What is a 1st class lever?
|
Distance from fulcrum to input force is GREATER than distance from fulcrum to the ouput force
|
|
Examples of 1st class lever?
|
seesaw, pliers, scissors, crowbar
|
|
Can a 1st class lever change the direction of the input force?
|
Yes
|
|
Second class levers always _____ force?
|
multiply
|
|
Do second class levers CHANGE DIRECTION?
|
NO
|
|
What are examples of 2nd class levers?
|
Wheelbarrow, nutcracker, bottle opener
|
|
____ class levers multiply distance but don't change direction of the input force?
|
3rd
|
|
What are examples of third class levers?
|
shovels, baseball bats, boat paddle
|
|
What is a simple machine that is made of 2 circular or cylindrical objects are fastened together and theat rotate about a common axis?
|
WHEEL AND AXLE
|
|
What are the advantages of the wheel and axel?
|
Multiplies the force but over a longer distance
|
|
How do you calculate the ideal mechanical advantage of the wheel and axel.
|
Use the radius of the wheel divided by the radius of the axle
|
|
What does the variation of the wheel and axle produce?
|
If you apply force on the axle then the input force is applied over a short distance and the output forcer is over a long distance
|
|
What kind of machine is a grooved wheel with a rope wrapped around it. ?
|
PULLEY
|
|
By pulling on the rope of a pulley you can change the ____and _____of the input force
|
amount
direction |
|
When you have a ___ pulley this changes the direction of the force only?
|
fixed
|
|
Does a fixed pully multiply the force?
|
no
|
|
A fixed pulley had the mechanical advantage of ____#
|
one
|
|
Moveable pulleys in force in the ____ direction as the output force.
|
same
|
|
Moveable pulleys ideal advantage is #____
|
2
|
|
The output force is greater or lesser than the input force?
|
Greater
|
|
Name a pulley system?
|
Block and Tackle
|
|
What is the ideal advantage of the block and tackle?
|
It is equal to the number of sections of the rope that supports the object.
|
|
A machine that utilizes 2 or more simple machines is a ____ ______.
|
Compound Machine
|
|
Describe a geer or system of geers?
|
toothed wheels that fit into one another
|
|
Most of the machines in your body are ______?
|
levers
|
|
Tendons are tough ______ tissue than connects _____ to ___.
|
connective tissue
muscles bones |