1. Matter can enter the system
1. Matter cannot enter the system
1. Energy is allowed into the system
2. Matter can leave the system
2. Matter cannot leave the system
2. Energy is allowed to leave the system
3. Solid boundaries must have a door or some kind of opening
3. Solid boundaries have no doors or lids
3. Energy can enter a solid boundary without an opening
4. Imaginary boundaries are always this type of system
4. These do NOT have imaginary boundaries
4. Energy can enter a system with an imaginary boundary
5. Objects can enter the system
5. Objects cannot enter the system
5. Without an energy input the system does not run or work
6. Objects can leave the system
6. Objects cannot leave the system
6. Energy input allows the system to work
7. An opening in the solid boundary allows objects to enter and leave the system
7. There are NO openings in the solid boundary to allow objects to enter or leave the system
7. There are two types: open systems and closed systems
8. Imaginary boundaries allow objects to enter and leave the system
8. They must be solid boundaries with no openings in the boundary
8. These must have energy to work and run
