Unit D: Section 1.0 - 2.0 Flashcards Preview

Grade 8: Science > Unit D: Section 1.0 - 2.0 > Flashcards

Flashcards in Unit D: Section 1.0 - 2.0 Deck (37):
1

What is an Archimedes screw?

A device that can pump fluids upward

2

What is a simple machine?

A tool or device made up of one basic machine

3

What are the six basic machines?

Lever
Inclined plane
Wedge
Screw
Pulley
Wheel and axel

4

Explain a lever

A ridged bar or plank that can rotate around a fixed point

5

What are the advantages of a lever?

With a lever you can move a larger load than without using it

6

What are the disadvantages of a lever?

You have to move a greater distance than the load does for this to work

7

What is an inclined plane?

A flat surface at an angle to another flat surface

8

What are the disadvantages of an inclined plane?

-You have to exert force over a longer distance compared to lifting straight up
-generally used for small inclines

9

What we advantages to an inclined plane?

It makes it possible to to lift heavy objects using small force

10

What is a wedge?

A simple machine that looks like an inclined plane but it forced into an object

11

What are the advantages to an inclined plane?

It increases the force you apply to an object

12

What are the disadvantages to a wedge?

A wedge can only be used in one direction

13

What is a screw?

A cylinder with a groove cut in a spiral in the outside

14

What are the advantages of a screw?

It helps increase the force you use. It can penetrate materials using relatively small force it can also convert turning motion into straight

15

What are the disadvantages of screws?

Most will move objects very slowly

16

What is a pulley?

A pulley consist of a wire, rope, or cable moving on a grooved wheel

17

What are the advantages of a pulley?

They can be linked together and they help you lift larger loads

18

What are the disadvantages to a pulley?

A pulley requires a long durable rope

19

What is a wheel and axel?

It is a combination of two wheels of different diameters. A longer motion on the wheel creates shorter but more powerful motion at the axel

20

What does The acronym 'EFL the ELF FEL' mean?

EFL-Effort Fulcrum Load
ELF-Effort Load Fulcrum
FEL-Fulcrum Effort Load

21

What is a machine?

A tool that helps humans do work

22

What is a hydraulic system?

It uses a liquid under pressure to move loads

23

Finish the sentence: To increase the force of the output piston...

the input piston had to move a greater distance

24

What is a complex machine?

A system in which all simple machines work together

25

What is each part in a complex machine called?

A subsystem

26

What are subsystems?

They are parts that perform specific functions such as breaking or steering

27

What is a linkage?

A belt or chain used to transfer energy from an energy source

28

What is a transmission?

A special type of linkage for transferring the energy from the engine to the wheels in large vehicles

29

What are gears?

A pair of wheels that have teeth that interlink

30

Which gear is the driving gear?

The gear that has force applied to it from the outside

31

What is the driven gear?

The gear that the driving gear applies force to

32

What is mechanical advantage?

It is the amount which the machine can multiply force

33

What is input force?

The force applied to the machine

34

What is output force?

The force the machine applies to an object

35

What is speed ratio?

A measure of how the speed of an object is affected by a machine

36

What is friction?

A force that opposes motion

37

What is efficiency?

A measurement of how well a machine or device uses energy