Spring 2021

Question 1

What are the 4 types of motion?

Answer 1

* Linear
* Rotary
* Oscillating
* Reciprocating

Question 2

What is rotary motion?

Answer 2

Circular motion from a central point

Question 3

What is linear motion?

Answer 3

Motion along a straight path

Question 4

What is oscillating motion?

Answer 4

Backward and forward motion along a curved path

Question 5

What is reciprocating motion?

Answer 5

Backward and forward motion along a linear path

Question 6

What is an example of a rotary motion?

Answer 6

Motion of a bike wheel

Question 7

What is an example of a linear motion?

Answer 7

Motion of a train

Question 8

What is an example of a oscillating motion

Answer 8

motion of a swing

Question 9

What is an example of a reciprocating motion?

Answer 9

motion of a jigsaw blade

Question 10

What is a class 1 lever?

Answer 10

The fulcrum is in the middle of the effort and the load

Question 11

What is a class 2 lever?

Answer 11

The load is in the middle between the fulcrum and the effort

Question 12

What is a class 3 lever?

Answer 12

The effort is in the middle between the fulcrum and the load

Question 13

What is an example of a class 1 lever?

Answer 13

Scissors

Question 14

What is an example of a class 2 lever?

Answer 14

Wheelbarrow

Question 15

What is an example of a class 3 lever?

Answer 15

Tweezers

Question 16

What is load?

Answer 16

The overall force that is exerted, usually by a mass or object, on a surface

Question 17

What is a fulcrum?

Answer 17

The fulcrum is the point on which the lever pivots

Question 18

What is effort?

Answer 18

Force used to move a load over a distance

Question 19

What are the 6 R’s?

Answer 19

Reduce
Reuse
Recycle
Refuse
Rethink
Repair

Question 20

What is “Reduce” in the 6 R’s?

Answer 20

A product where materials have been reduced or replaced by more sustainable types

Question 21

What is “Reuse” in the 6 R’s?

Answer 21

A product that could be reused as something else

Question 22

What is “Recycle” in the 6 R’s?

Answer 22

A product that uses recycled materials

Question 23

What is “Refuse” in the 6 R’s?

Answer 23

A product that uses un-necessary materials and could be replaced by another product that uses more sustainable materials

Question 24

What is “Rethink” in the 6 R’s?

Answer 24

A product that could be redesigned or remanufactured using more sustainable materials

Question 25

What is "Repair" in the 6 R's?

Answer 25

A product that could be repaired rather than thrown away or replace

Question 26

What are pulley systems used for?

Answer 26

Pulley systems can be used to connect rotary systems together using belts, they can also be used to change the speed within a system by using different sized pulleys

Question 27

What is the difference in speed between 2 pulleys called?

Answer 27

The Velocity Ratio

Question 28

What does a mechanical advantage do?

Answer 28

Mechanical advantages allows humans to perform tasks much easier in terms of the force they need to apply

Question 29

What is the equation for the velocity ratio in gears?

Answer 29

velocity ratio = no. teeth on driven sprocket / no. teeth on driver sprocket

Question 30

What is the driven sprocket?

Answer 30

The driven sprocket is the sprocket that is driven by the chain

Question 31

What is the driver sprocket?

Answer 31

The driver sprocket is the sprocket that drives the chain

Question 32

What is the velocity ratio if the driver gear has 60 teeth and the driven gear has 12 teeth?

Answer 32

``` 12/60 = 0.2/1 0.2:1 = 1:5 ``` 1:5

Question 33

What is the velocity ratio if the driver gear has 48 teeth and the driven gear has 24 teeth?

Answer 33

``` 24/48 = 0.5/1 0.5:1 = 1:2 ``` 1:2

Question 34

What is the velocity ratio if the driver gear has 20 teeth and the driven gear has 40 teeth?

Answer 34

40/20 = 2/1 2:1 2:1

Question 35

What is it called when gears fit together?

Answer 35

meshing

Question 36

What happens to the direction of rotation when 2 gears are placed next to each other?

Answer 36

The direction of rotation is changed

Question 37

What can solve the issue of the direction of rotation being changed when 2 gears are placed next to each other?

Answer 37

An idler gear between the 2 main gears

Question 38

Why might a belt-driven pulley system be used over a gear chain system?

Answer 38

Belt-driven systems are simpler as they do not need gear teeth

Question 39

Why are gears used within a mechanical system?

Answer 39

They change the speed and create a mechanical advantage

Question 40

Explain how an idler gear works

Answer 40

An idler gear is placed between 2 gears when you do not want to change the direction of rotation. The direction is changed between the gear 1 and the idler gear. The direction is then switched back to the original direction between the idler gear and gear 2

Question 41

What is the equation for the effort in a pulley system?

Answer 41

effort = load / number of pulleys

Question 42

Why is the effort required calculated different to the actual effort required

Answer 42

Within the system there is friction, this will increase the perceived weight and therefore the effort

Question 43

What type of linkage is it when all the linkages move together in the same direction?

Answer 43

Parallel motion linkage

Question 44

What type of linkage is it when the linkage changes motion around an angle?

Answer 44

Bell crank linkage

Question 45

What type of linkage is it when the linkage changes the direction of motion?

Answer 45

Reverse motion linkage

Question 46

What type of linkage is it when the linkage changes rotary motion into reciprocating motion?

Answer 46

crank and slider linkage

Question 47

Linkages are mechanisms that use rigid parts to:

Answer 47

\*Provide uniform movement of different components \*Change the direction of a force/motion \*Transform it into a different motion \* Change the magnitude of a force

Question 48

Explain how a Parallel motion linkage works

Answer 48

Parallel motion linkages use two fixed pivots to make the input and output travel in the same direction, through a link arm. Each fixed pivot has a moving pivot on either side, allowing the movement and power to go backwards and forwards. Changing the placing of the fixed pivots changes the amount of force exerted, while keeping the direction the same.

Question 49

Explain how a Bell crank linkage works

Answer 49

The fixed pivot is at a 90\* angle from both the input and output, so it forces the direction of force through 90\*

Question 50

Explain how a Reverse motion linkage works

Answer 50

A fixed pivot forces the change in direction

Question 51

Explain how a crank and slider linkage works

Answer 51

A fixed pivot is attached to a crank, which turns around and pushes and pulls a slider

Question 52

What does a Parallel motion linkage do?

Answer 52

input and output travel in the same direction

Question 53

What does a Bell crank linkage do?

Answer 53

Bell crank linkages change the direction of force through 90°

Question 54

What does a Reverse motion linkage do?

Answer 54

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

Question 55

What does a crank and slider linkage do?

Answer 55

Crank and slider linkages change rotary motion into reciprocating motion

Question 56

What are 3 types of gears?

Answer 56

\*Worm Gear \*Bevel Gear \*Rack and Pinion Gear

Question 57

What does a worm gear do?

Answer 57

Worm gears can be used to transfer motion by 90\*. A worm gear only has 1 "tooth" that corks like a screw thread

Question 58

What does a bevel gear do?

Answer 58

Bevel gears change the direction of rotation by 90\* but use different sized gears to change the speed of rotation

Question 59

What does a rack and pinion gear do?

Answer 59

A rack and pinion gear changes rotary motion into linear motion. This is usually a fairly small linear movement that goes in 1 direction and then back again

Question 60

What is an example of a worm gear?

Answer 60

tuning mechanism for a guitar

Question 61

What is an example of a bevel gear?

Answer 61

Bevel gears are used on roller shutter doors

Question 62

What is an example of a rack and pinion gear?

Answer 62

steering system on many cars

Question 63

What is the equation for the output speed of a gear?

Answer 63

Output speed = input speed ÷ velocity ratio

Question 64

What type of linkage is this?

Answer 64

Bell crank linkage

Question 65

What type of linkage is this?

Answer 65

Crank and slider linkage

Question 66

What type of linkage is this?

Answer 66

Reverse motion linkage

Question 67

What type of linkage is this?

Answer 67

parallel motion linkage