Mechanical devices

Question 1

what is linear movement

Answer 1

when something moves in a straight line

Question 2

rotary movement

Answer 2

where something moves around an axis or pivot

Question 3

reciprocating movement

Answer 3

a repeated up and down or back and forth motion

Question 4

oscillating movement

Answer 4

a curved backwards and forwards movement that swings on an axis or pivot point

Question 5

what are levers

Answer 5

devices that use mechanical advantage to make lifting or applying pressure easier

Question 6

what is effort

Answer 6

the amount of force applied by the user

Question 7

what is the fulcrum

Answer 7

where the lever pivots

Question 8

what is the load

Answer 8

the weight that needs to be moved

Question 9

what is mechanical advantage

Answer 9

the amount of help you get using a machine in comparison to doing something with just human effort

Question 10

equation for calculating mechanical advantage

Answer 10

load/effort

Question 11

what are first class levers

Answer 11

levers with the fulcrum in the middle, between the effort and load

Question 12

what are second class levers

Answer 12

levers with the load in between the effort and fulcrum

Question 13

how do first class levers work

Answer 13

If the load is closer to the fulcrum it becomes easier to lift

Question 14

examples of first class levers

Answer 14

seesaw, crowbar, scissors

Question 15

When a lever is balanced it has equilibrium

Answer 15

the load is balanced on either side.

Question 16

examples of second class levers

Answer 16

wheelbarrow, nutcrackers, some bottle openers

Question 17

how do second class levers work

Answer 17

The closer together the fulcrum and load are, the easier it is to lift the load

Question 18

what are third class levers

Answer 18

levers with the effort between the fulcrum and the load

Question 19

examples of third class levers

Answer 19

tweezers or fishing rods

Question 20

how do third class levers work

Answer 20

If the effort and the fulcrum are further apart, it becomes easier to lift. A third order lever does not have the mechanical advantage

Question 21

what are linkages

Answer 21

a system of links, can be levers joined together

Question 22

how do push/ pull linkages work

Answer 22

they use two fixed pivots to make the input and output travel in the same direction, through a link arm
- Changing the placing of the fixed pivots changes the amount of force exerted, while keeping the direction the same

Question 23

examples of push/pull linkages

Answer 23

a toolbox with drawers opens up

Question 24

what do bell crank linkages do

Answer 24

change the direction of force through 90

Question 25

how can you change the output force of a bell crank

Answer 25

by moving the fixed pivot

Question 26

examples of bell crank linkages and why

Answer 26

used in bicycle brakes, the rider can pull the brakes from the handlebars, which changes direction through the bell crank to make the brake pads touch the wheels.

Question 27

what is reverse motion/linkage

Answer 27

Reverse motion linkages change the direction of input so that the output goes the opposite way

Question 28

what is crank and slider

Answer 28

change rotary motion into reciprocating motion, used in car engines

Question 29

what is a cam mechanism

Answer 29

a shaped part of a pivot which converts reciprocating motion to rotary motion

Question 30

what is a cam attached to

Answer 30

attached to a crankshaft, which rotates

Question 31

what is a follower

Answer 31

something that touches the cam and follows the shape, moving up and down