You are conducting a physics demonstration where you need to slide a heavy block across a surface with minimal resistance. You decide to use a gas to reduce friction. Which of the following methods would be most effective in demonstrating the principles of reduced friction using gas?

The best way to show how gas can lower friction is to put the block on a thin sheet of air—an air table—so the air forms a very thin cushion between the block and the surface. The air pressure lifts the block just enough that its weight is supported by the gas, leaving almost no contact area for friction to act. This clearly shows that friction is linked to the amount of direct contact. For example, sliding a heavy crate across an air‑cushioned table requires very little force compared with sliding it on a normal table.