UNIT 8 technology part 2

Question 1

name the two types of motions and their axises

Answer 1

1. transational (Tx,Ty,Tz)
2. rotational (Rx, Ry, Rz)

Question 2

4

list the link characteristics and their questions

Answer 2

1. Direct or indirect (do the parts require something else to hold them together?)
2. Rigid or flexible (is the material linking the parts together a spring?)
3. Removable or Non-removable (can the object be taken apart without causing damage to the pieces)
4. complete or partial ( is movement possible between the two parts?)

Question 3

list and explain each guiding

Answer 3

1. Translational guiding: ensures the straight-line motion of moving parts
2. Rotational guiding: ensures the rotational motion of moving parts
3. Helical guiding: ensures the transational motion of a moving part while it rotates about the same axis.

Question 4

5

list the constraints and do the symbol

Answer 4

1. compression (crush)
2. tension (stretch it)
3. rotation (twist it)
4. deflection ( bend it)
5. shearing ( cut it)

Question 5

7

list the mechanical properties and brief explain

Answer 5

1. hardness (resist indents)
2. elasticity (return to og shape after constaint)
3. malleability ( flattened or bent no break)
4. fragility (break without deformation under constraint)
5. resilience ( resist shocks no break)
6. ductility ( stretched without breaking)
7. stiffness ( retain shape when constraint)

Question 6

plus exemple

what is a composite material?

Answer 6

formed from two or more different materials in order to obtain a new one with improved porperties compared to those of the original materials

Question 7

what is the main difference between thermoplastic and thermosetting plastic

Answer 7

• thermoplastics can be melted an reshaped while thermosetting can NOT
• thermoplastics in drawing arent connected, thermosetting ARE

Question 8

6

list the properties of materials and brief explenantion

Answer 8

1. lightness (low-density)
2. chemical neutrality (not chemically active ble to reisst them)
3. electrical conductivity (able to conduct electric current)
4. heat resistance ( resist heat stays the same)
5. corrosion resistance ( resist corrisive stuff slats)
6. thermal conductivity ( can transmit heat)

Question 9

give exemples of thermoplastics and properties

Answer 9

• lego, PVC pipes, food ocntainers, grocery bagsm plexiglass
• chemical neutrality, elasticity, lightness, resilience, corrosion resistance

Question 10

give exemples of thermosetting and properties

Answer 10

• melamine plates, rubber, epoxy, pot handles, fiberglass
• hardness, resilience, heat resistance, stiffness

Question 11

difference between motion transmission and transformaton

Answer 11

• transmission only transmits rotational motion while transformation transmits rotation to translation vise versa

Question 12

how is a system reversible

Answer 12

if the driven component can become the driver

Question 13

difference between driver and driven

Answer 13

driver receives the force, while driven receives the motion, tranferred from the driver

Question 14

intermediate is

Answer 14

located between the driver and the driven component

Question 15

how do you calculate speed changes using something

Answer 15

the gear ratio is #teeth on the driver/#teeth on the driven

Question 16

3 types of deformation and brief explain

Answer 16

1. elastic ( temporary)
2. plastic (permanent)
3. fracture (breaks)