1. The demonstration balance is made from wood so it’s easily to get damages and then it’s very easy to make error.
2. The assorted weights that the experimenters use may not be accurate as the labels because of rusts and damages.
3. The hooks hanging on the demonstration balance may not have the same weight. These can cause errors too.
4. The experimenters can’t see very well. Though it isn’t balanced, the experimenters may see that it is balanced.
5. When I weight mass on the digital scale, it is inaccurate because the surrounding in the room caused errors.