Mechanisms

Question 1

gear ratio

Answer 1

relationship between teeth on 2 gears

Question 2

rotary motion

Answer 2

turning around in a circle

Question 3

linear motion

Answer 3

moving in a straight line

Question 4

recipricatory

Answer 4

linear motion in 2 directions (moves back an forth on a given track)

Question 5

oscillatory

Answer 5

swinging from side to side along an arc

Question 6

mass

Answer 6

amount of material in an object

Question 7

weight

Answer 7

measure of gravity pull on an object

Question 8

gravity

Answer 8

force of attraction between all objects of matter

Question 9

weight equation

Answer 9

weight = mass x acceleration due to gravity

Question 10

work

Answer 10

work is done when a force causes an object to move (mount of mechanical energy transferred by force to an object)

Question 11

watt

Answer 11

unit of measurement for power

Question 12

calculate watt

Answer 12

1 watt = 1J/S

Question 13

Lever

Answer 13

rigid bar pivots around a fulcrum used to carry a load

Question 14

what does a lever do

Answer 14

magnifies/ increases movement( small effort/ large distance)

Question 15

class 1 lever

Answer 15

load - fulcrum - effort

Question 16

class 2 lever

Answer 16

effort - load - fulcrum

Question 17

class 3 lever

Answer 17

load - effort - fulcrum

Question 18

mechanical advantage

Answer 18

how a mechanism helps eg - lifts a heavier load than you would be able to

Question 19

moment of force

Answer 19

product of force and perp dist between line of action and fulcrum

Question 20

material testing - why?

Answer 20

-quality control
-standardisation of components
-values for properties eg strength
-success of heat treatments can be measured

Question 21

vickers hardness test

Answer 21

-square based pyramid pushed into material,
- diagonal length of indent is measured
- converted to Vickers hardness scale

Question 22

brinnell hardness test

Answer 22

-spere is pushed into material
-diameter of crevice created is measured

Question 23

rockwell hardness test

Answer 23

• cone pushed into material
• measurement taken from dial on machine

Question 24

izod impact test

Answer 24

notch on specimen from pendulum
-specimen held vertically in vice and struck with pendulum
-striking force 167 J

Question 25

charpy hardness test

Answer 25

specimen held horizontally in vice
-notch on opposite side to pendulum strike
-striking force 300J

Question 26

tensile testing

Answer 26

how much it stretches before it snaps

Question 27

hardness tests?

Answer 27

Vickers, Brinell, Rockwell

Question 28

Impact tests

Answer 28

Charpy, Izod

Question 29

additive manufacturing

Answer 29

cartoon of 3d products layer by layer

Question 30

subtractive manufacturig

Answer 30

manufacturing by removing material

Question 31

linkages

Answer 31

used to change direction or type of motion, or size of force in a mechanism (diagrams)

Question 32

springs

Answer 32

pushes or pulls objects together - tension and compression springs

Question 33

belt an pulley system

Answer 33

rope belt runs around two wheels

Question 34

RPM

Answer 34

revolutions per minute

Question 35

fixed pulley

Answer 35

one fixed wheel and one rope used to lift objects

Question 36

movable pulley

Answer 36

free axle - free to move up and down in space

Question 37

compound pulley systems

Answer 37

combination of moveable and fixed pulleys to increase mechanical advantage