[QUOTE=MrShoeBoy;18080]So I have a sealed jar with a butterfly inside.
1. Is the jar heavier with the butterfly sitting on the bottom or side? this one
OR
2. Is the jar heavier with the butterfly flying around inside the jar? the weight is not measurable
OR
3. Its always the same weight regardless if the butterfly is sitting or flying. the mass is always the same but not the weight
i'm guessing but it makes sense to me