To celebrate our amazing Tipsi Tray being made available, I thought I would explain how it works. Everyone here knows that the Single Handed Tipsi Tray was made to hold your drinks and anything else you want without them falling, spilling or breaking. The tray is non slip and the handle is made for perfect balance and durability. So let's see why it works that way. It’s all about the physics. Hopefully this will be an interesting insight into how your drinks hang on to that tray!
When you hold an open top drink, whether that be a cup of coffee, a glass of water or a beer there is always the chance of spilling it. Because of Newton’s Third Law we know that if a force is applied abruptly to one side of the cup, then the liquid inside the cup exerts a force of equal measure but in the opposite direction. There is also the force of gravity acting on the cup and liquid in a downward motion.
Basically if you knock the side of the cup then you enact a force on that side that then enacts the same force on to the liquid inside. This force causes it to splash to the opposite side and leave the edge of the cup, meaning it spills.
When you put the drink on the Tipsi Tray, you are holding the handle at the top and causing a new centre point at the top of that handle. By holding it loosely you allow the tray to move freely and if any lateral force was applied to your hand (someone bumped into you) then this does not translate to the handle or the tray or the side of the cup. Everything on the tray will swing together in the same direction. Gravity and the normal force end up working together and go in the same direction as the force that knocked the cup resulting in equal acceleration to the tray, cup and liquid meaning no spill.