Machines are objects that use energy to make work easier. They have various uses including applying force, transporting things, heating/cooling things, communicating, and processing information. Simple machines like the pulley, lever, and inclined plane have one or a few parts and use human energy, while complex machines like bikes have many interconnected parts. All machines require energy from various sources like humans, electricity, water, or wind to operate.

2. Machines are objects we use to
make work easier.

3. All machines use energy:
•from people (screwdriver, wheelbarrow…)
•electrical (microwave, washing machine…)
•from water (watermills…)
•from wind (windmills…)

4. Uses:
• to apply force.
•to transport things.
•to heat or cool things.
•to communicate.
•to process information.

5. SIMPLE MACHINES
•They have one part or just a few parts.
•They use energy from people to work.
The pulley The leverThe inclined
plane

6. The pulley:
•We use it to lift and lower heavy objects.
•It has got an axle.

7. The inclined plane:
•It is a ramp.
•We use it to move heavy things up or
down.

8. The lever:
•It is a rigid bar.
•It has got a pivot point.
•We use it to lift heavy objects.

11. COMPLEX MACHINES
They are made up of many operating parts.

12. A bike is a complex machine.
It has got two pedals, a handle bar, two
wheels, teeth, gear and a chain.

14. Look at these machines.
•What are their names?
•Are they simple or complex
machines?
•We use them to…
• to apply force.
•to transport things.
•to heat or cool things.
•to communicate.
•to process information.