ch 12-13 Flashcards Preview

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Flashcards in ch 12-13 Deck (47)
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1

work

when you exert a force on an object that causes the object to move some distance

2

how do you know if work is being done on an object

if an object moves in the same direction in which the force is exerted

3

joule

measurement for work, 1 joule is to move an object a distance of one meter

4

power

the rate at which work is done

5

a machine makes work easier by changing at least one of three factors, what are the three factors

a machine may change the amount of force you exert, the distance over which you exert your force, or in the direction in which you exert your force

6

machine

a device that allows you to do work in a way that is easier

7

input force

the force you exert on the machine

8

input distance

the distance the input force moves the machine

9

output force

the force the machine exerts on an object

10

output distance

the work the machine dose over another distance

11

input work

the input force times the input distance

12

output work

the output force times output distance

13

mechanical advantage

the number of times a machine increases a force exerted on it

14

efficiency

compares the output work to the input work of machine

15

what are the six basic types of simple machines

incline plane, wedge, screw, lever, wheel and axle, and pulley

16

most of the machines in your body are what?

levers that consist of bone and muscles

17

what is the ideal mechanical advantage of a compound machine

it is the product of the individual ideal mechanical advantages that make it up

18

incline plane

a flat, slope

19

wedge

a device that is thick at one end and tapers to a thin edge at the other end

20

screw

can be thought of as an incline plane wrapped around a cylinder

21

lever

is a ridged bar that is free to pivot or rotate on a fixed point

22

fulcrum

the fixed point that a lever pivots around

23

wheel and axle

a simple machine made out of two circular or cylindrical objects fasted together that rotate about a common axis

24

pulley

a simple machine made of a grooved wheel with a rope or cable rapped around it

25

compound machine

a machine that utilizes two or more simple machines

26

what are two basic types of energy

kinetic and potential

27

energy

the ability to do work or cause change

28

kinetic energy

the energy an object has due to its motion

29

potential energy

stored energy that results from the position or shape of an object

30

gravitational potential energy

potential energy related to an objects hight