Conservation of energy

Cards (9)

Conservation of energy principle
Energy can be transferred, usefully stored or dissipated, but can never be created or destroyed
Energy can only move between different objects and different forms
Charging a phone
1. Electrical energy from the main supply travels along the wire
2. Gets transferred to the chemical energy store in the phone's battery
Using a phone
1. Chemical energy is converted back to electrical energy
2. Electrical energy flows around the circuit
3. Powers the different parts like the screen and speaker
Energy transfer in the screen
Electrical energy is converted to light energy
Energy transfer in the speaker
Electrical energy is converted to sound energy
In a closed system, the overall energy doesn't ever change
Open system 
Where energy can be transferred into surroundings
Closed system 
Where transfer of matter in and out is not allowed