World Of Technology

Machine

Machines are devices that make work easier and faster.

Simple Machines

There are seven types of simple machines:

1. Wheel and axle

Examples of Wheels and Axles:

• Cars
• Roller Skates
• Wagons
• Door Knobs
• Gears in Watches, Clocks, and Bicycles

2. Lever

2.1 First Class Levers
An example of this type is a seesaw. The load is the person that goes up, and the effort applied is the weight of the person that goes down. The fulcrum is in the center in between them.

Seesaw

2.2 Second Class Lever 
An example of a Second Class Lever is a can opener. The difference from the first class lever is that the fulcrum is on the end, instead of in the middle.

Can Opener

 2.3 Third Class Lever
 An example the Third Class Lever is a fishing rod. The load is the fish; the handle end is the fulcrum.

3. Wedge

A wedge is a triangular shaped round tool, a compound and portable inclined plane.It can be used to separate two objects or portions of an object, lift an object, or hold an object in place.

4. Pulley

A pulley is a wheel on an axle that is designed to support movement of a cable or belt along its circumference.

These are different types of pulley systems:

• Fixed: A fixed pulley has an axle mounted in bearings attached to a supporting structure. A fixed pulley changes the direction of the force on a rope or belt that moves along its circumference. Mechanical advantage is gained by combining a fixed pulley with a movable pulley or another fixed pulley of a different diameter.

Fixed Pulley

Movable: A movable pulley has an axle in a movable block. A single movable pulley is supported by two parts of the same rope and has a mechanical advantage of two.

Movable Pulley

Compound: A combination of fixed and a movable pulleys forms a block and tackle. A block and tackle can have several pulleys mounted on the fixed and moving axles, further increasing the

    mechanical advantage.

.

Compound Pulley

5.Gear

A gear is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque.

Watch or clock

A bicycle chain

A drill

6. Inclined plane

An inclined plane is a flat supporting surface tilted at an angle, with one end higher than the other, used as an aid for raising or lowering a load. Inclined planes are widely used to move heavy loads over vertical obstacles; examples vary from a ramp used to load goods into a truck, to a person walking up a pedestrian ramp, to an automobile or railroad train climbing a grade.Moving an object up an inclined plane requires less force than lifting it straight up, at a cost of an increase in the distance moved.

7. Screw

 The screw has a spiral inclined plane called thread. It is a mechanism that converts rotational motion to linear motion, and a torque (rotational force) to a linear force. The screw passes through a hole in another object or medium, with threads on the inside of the hole that mesh with the screw's threads. When the shaft of the screw is rotated relative to the stationary threads, the screw moves along its axis relative to the medium surrounding it; for example rotating a wood screw forces it into wood. In screw mechanisms, either the screw shaft can rotate through a threaded hole in a stationary object, or a threaded collar such as a nut can rotate around a stationary screw shaft.

Bottle

Wine opener

Stair