Linear Motion

NEW WORDS 

1º Mechanism: Mecanismo
2º Transmitting:Transmitiendo
3º Linear motion: Movimiento lineal 
4º Rotary motion: Movimiento rotatorio
5º Reciprocating motion: Movimiento recíproco
6º Oscillating motion: Movimiento oscilante 

See-saw

7º Pulley: Polea
8º Lever: Palanca
9º See-saw: Balancín







                                                      

                                                     10º Pliers: Alicates
 11º Tweezers: Pinzas
 12º Nutcrackers: Cascanueces
 13º Staple removers: Quitagrapas
 14º Crowbar: Palanca

 15º Oar:Remos

 16º Wheelbarrows: Carretilla

 17º Paper punch: Perforadora de papel
 18º Staple removers: Quitagrapas
                                                                                     

        MACHINES AND MACHANISM

A simple pair of scissors is a machine. 

Not all machines are complex like airplanes. We use a lots of machines in our everydays lives without realising.

Machine: A set of parts that work together 

5 Types of Stresses 

CIomprension: For example when we lwan an a table, it undergoes compraqssive stress; colums are also subject to compresive. 
Tension: For example, when two people pull on an object. 
Bending:
Torsion: For example, two people hold a towel at either end and twist it to wring it out, a crank is also subjected to torsion 

CONDITIONS FOR A STRONG STRUCTURE 

• Strong 
• Rigid 
• Equilibrum 
• Stable 

EXERCICES

1.       Copy and complete the following table in the notebook:

Types  structures	Examples
Mass	Wals, dams, etc…
Frame	Sturcture of a building
Truss	Cranes, electricity pylons, etc…
Suspended	Tents, marquees, etc…

2.       Have you ever seen a structure that uses cables? Write down the names of the ones that you can remember or the ones that you can see and draw them in your notebook.

Yes, in the Cable Car of Seville

3.    When a person sits on a chair, the stress that the chair has to withstand is due to the person, wheareas the strength is the chair,s ability to withstand the load without breaking. Indicate which is the strength and which is the stress in these two exaples:                                         

 a) A wardrobehanging from a rope                                                        
Rope: Stress
Wardrobehanging: Strenght                    

 b) A twisting telephone cord.

       Telephone: Strenght

7.    Which types of stress do the following elements and activities have to support: a rope with a weight hanging off it, a man pushing a cabinet, tightening a screw, cutting our fingernails.
Tension, comprension and shear

9.    Write a short description of three objects using one of the following adjectives for each object: rigid, elastic and plastic. Explain how these properties allow the objects to fulfil their function or make them suitable for their purpose.
Plastic: Deforms and stays deformed (Gum)

Rigid: Does not deform (Stone)

Elastic:  Deforms but then returns to original shape (Tights)

11. Copy and complete the following tabe in your notebook with objects that have the properties shown in the right-hand colum.

Object	Proportipes
Brick	Rigid
Slime	Deformable
Elastic Band	Elastic
Water Bottle	Plastic

12.  Think about the following objects and state whether they are rigid, plastic or elastic: ballon or elastic, empty drinks can, window frame, clay, catapult, door.

Plastic: Water Bottle

Elastic: Elastic Band 

Rigid: Nut

                             Learning HTML 

And you finish!