FORMS OF ENERGY
Mechanical energy
DEFINITION: Energy that produces movement.
EXAMPLES: walk, ride the bike, car, washing machine, change the direction of an object (ball).
TYPES:
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Potential energy: Energy is stored. Example: muscle, battery
-
Kinetic energy: energy in movement. Example: walking, phone vibrates.
Chemical energy
DEFINITION: The energy is stored in some substances/matter.
EXAMPLES:
-Pasta: energy is stored in the form of carbohydrates
-Mobile phones: energy is stored in the battery
TRANSFORMATIONS:
Chemical energy can transform into light, electricity, heat, movement (kinetic)
Examples:
Batteries: Chemical energy (Battery) to electricity
Camping stove: Chemical energy (Gas) to heat
Car: chemical energy (fuel)to movement (kinetic)
Thermal energy
DEFINITION: This is the energy in the form of heat.
HOW CAN WE KNOW THE AMOUNT OF THERMAL ENERGY? : Temperature
CHANGES:
-Temperature variation
.Expansion an contraction
-Change of state
-Chemical changes (Ex: when we cook)
HEAT TRANSFER: Energy involved in transforming heat from one object to another.
How?
-From the warmer object to the cooler object.
Ways?
-By contact
-At a distance
LUMINOUS/ LIGHT ENERGY
DEFINITION: This is the energy in the form of light.
LUMINOUS ENERGY CAN CAME FROM:
•Natural light resources
•Sun
•Stars
•Artificial resources
•Light bulbs
•Leds
•Torches
LIGHTS
-Travel fast, straight line in every direction
-Depending on the properties of the object
-Reflection:
-Light travels through air and hits opaque objects
-Example: Mirror
-Refraction:
-Light passes through transparent substances. Light energy changes direction slightly.
-Example: Glass with water
-Dispersion:
-Light waves travel through substances that separate white light into its different colours.
-Ex: Glass prism
SOUND ENERGY
DEFINITION: It is an energy wave that makes things vibrate. Sound tranfers kinetic energy to the objects around it.
•Sounds can travel through
•Solids: metal, stone, wood.
•Liguids: water
•Gases: air
•Sounds can not travel through
•Vacuum: there is no air.
NUCLEAR ENERGY
DEFINITION: It is the energy stored in atoms, the smallest type of matter.
WHERE CAN WE FIND IT?
-Natural:
•Sun
•Earth: uranium
•Man made:
•Nuclear power plants
ELECTRICAL ENERGY
DEFINITION: It is associated with electrical charges and their movement
TYPES
-Acumulated electricity:
•Electrical charges do not move from one object to another
•Ex: Static electricity
•Flow electricity
•Electrical charges move from one place to another
•Ex: Electric current through cables, plugs...
ELECTRIC CIRCUITS:
