RESISTANT ELEMENTS IN STRUCTURES

VERTICAL
PILLAR: a larg post that helps to holp up something (roof  or building)

COLUMN:  a long post made of steel, stone, marble, etc., that is used as a support in a building

HORIZONTAL

BEAM:  a long piece of heavy often squared timber suitable for use in buildings.

JOIST: small beam.

FOUNDATION

FOOTING:  an elargement at the lower end of a foundation in a wall, pier or column to distribute the load.

SLAB: a flat rectangular architectural element that is usually formed of a single piece of mass: concrete.


WRITE THE NAME OF THE FOLLOWING ELEMENTS

1. 

2.

3.

4.

5.

6.

7.

PULLEY

1. FIX PULLEY

A fixed pulley is a wheel that has a groove around it into which a rope, chain or belt fits. It rotates around an axle that is fixed to an inmobile surface.

A fixed pulley is ballanced when the effort F is equal to the resistance of the load, R:

       F=R

2. MOVABLE PULLEY

A movable pulley is a set of two pulleys- one is fixed while the other can move in a linear direction.

A movable pulley is balanced when it satisfies this equation:
       
            R
F = -----
        2

3. COMPOUND PULLEY

This is a system of fixed and movable pulley, often called block and tackle.

        R
F=--------
       2n
n= number of movable pulleys.