1. Energy Bar Graphs Qualitative Examples
A ball rolls down the hill.
Initial
Energy Flow Diagram
Final Ek Eg Ee Ek Eg Ee
Ediss
System Ball, Hill, Earth Friction ?
System Ball, Hill, Earth Friction yes
System Ball, Hill Friction ?
System Ball, Friction ?
System Friction ?
Since the system is isolated (no external forces), energy is conserved.

2. Energy Bar Graphs Qualitative Examples
Consider a Spring stretched to the right from a rest position.
Initial
Energy Flow Diagram
Final Ek Eg Ee Ek Eg Ee
Ediss
System Spring, Wall, Earth
System
System Spring
System Spring, Wall

3. Energy Bar Graphs Qualitative Examples
A box is lowered.
Initial
Energy Flow Diagram
Final Ek Eg Ee Ek Eg Ee
Ediss
System Box, Pulley, Earth
System Box, Pulley
System
System Box,