Conservation of Energy

Study Notes

Definition

The law of conservation of energy states that the total energy of an isolated system remains constant over time.
Energy cannot be created or destroyed, only converted from one form to another.

Types of Energy

Kinetic Energy (KE): the energy of motion
Potential Energy (PE): stored energy, can be gravitational, elastic, or chemical
Thermal Energy (TE): the energy of heat
Electrical Energy (EE): energy associated with the movement of charged particles
Chemical Energy (CE): energy stored in the bonds of atoms and molecules

Energy Conversion

Energy can be converted from one form to another, but the total energy remains constant
Examples:
- Mechanical Energy (KE + PE) → Thermal Energy (friction)
- Electrical Energy → Kinetic Energy (electrical motor)
- Chemical Energy → Kinetic Energy (combustion)

Systems and Energy Transfer

Isolated System: no energy transfer across boundaries
Closed System: energy can be transferred across boundaries, but matter cannot
Open System: both energy and matter can be transferred across boundaries
Energy Transfer: occurs through work, heat, or mass transfer

Conservation of Energy Equation

ΔE = Q - W
- ΔE: change in total energy
- Q: heat added to the system
- W: work done on the system

Importance of Conservation of Energy

Fundamental principle in physics and engineering
Applied in various fields, such as:
- Energy production and consumption
- Mechanical systems and machines
- Thermodynamics and heat transfer

Description

Understand the fundamental principle of energy conservation, types of energy, energy conversion, and energy transfer. Learn how energy is conserved in isolated, closed, and open systems, and its importance in physics and engineering.