Forms of Energy
This is the form of energy associated with the movement of an object.
Kinetic Energy
In science, this is the general term for any device that changes energy from one form to another.
energy converter
In a 3-part system, this is the term for the energy that goes into the converter to make it work.
input energy
This scientific law states that energy cannot be created or destroyed, only changed in form.
Law of Conservation of energy
This term describes a measure of how much input energy a machine actually turns into useful output energy.
efficiency
This form of stored energy is found in food, batteries, and fossil fuels like gasoline.
Chemical Energy/Potential Energy
A toaster is specifically designed to convert electrical energy into this form of energy.
What is thermal energy (or heat)
Picture a human running a race, this acts as the "converter."
human body (or muscles)
In almost all mechanical energy conversions we've looked at in class, wasted energy escapes into the environment primarily in this form.
Thermal energy (or heat)
The reason why no machine in the real world can ever be completely 100% efficient
Waste Energy (Heat/friction)
This form of energy travels in waves and includes visible light, X-rays, and microwaves.
Electromagnatic/Radiant energy
This common everyday device acts as a converter that changes electrical energy into sound energy.
What is a speaker (or headphones)- Answers may vary
When analyzing a gas-powered lawnmower, this is the initial input energy.
What is chemical energy
This physical force between moving parts is the main reason mechanical machines generate waste heat.
Friction
Upgrading a home’s insulation improves its energy efficiency by reducing the loss of ______ to the outside.
Heat (Thermal energy)
A heavy book sitting on the top shelf of a tall bookcase possesses this specific type of stored energy.
What is gravitational potential energy?
During photosynthesis, plants act as converters by changing solar/light energy into this form of energy.
Chemical energy (Glucose)
In a wind turbine system where kinetic energy from the wind is the input, this is the intended, useful output energy.
electrical energy
If exactly 100 Joules of electrical energy enter a light bulb, exactly this much total energy (useful + waste) must exit the bulb.
100 Joules?
If a car engine is described as being 25% efficient, it means the remaining 75% of the fuel's energy was converted into this.
Waste energy
This is the specific type of energy stored in a stretched rubber band or a compressed metal spring.
Elastic or potential Energy
A solar panel operates by converting light energy from the sun directly into this useful output energy.
What is electrical energy?
In a battery-powered flashlight system, the sequence is Chemical Energy --> Flashlight --> and finally, this useful output energy.
Light Energy
Mechanics add this to car engines to reduce friction, which directly decreases the amount of wasted thermal energy.
Oil/grease or lubricant
If Machine A and Machine B both successfully perform the exact same task, the more efficient machine is the one that requires less of this.
Input energy (or fuel/potential energy)