| B4-1 | Funnel and ball. |
| Purpose: | To demonstrate pressure change with flow. |
| Description: | A strong blast of air is sent backwards through a funnel. A ball placed in the apex of the funnel will not be blown out and cannot be tipped out when the funnel is inverted. |
| References: | Fj-4. |
| Equipment: | funnel connected to a tube, air supply and a ball. |