1. Rubber sucker– this is a shallow rubber cap. Before use it is moistened to get a good
seal then pressed firmly on a smooth surface so that the air inside is pushed out. The
atmospheric pressure will then hold it firmly
against the surface as shown below. They are used by
printing machines to lift papers, lifting glass panes,
2. Drinking straw– when a liquid is drawn using a straw air is sucked through the straw
to the lungs. This leaves the space in the straw partially evacuated. The atmospheric
pressure pushing down the liquid in the container becomes greater than the
pressure inside the straw and this forces the liquid into your mouth.
3. The syringe– they work in the principle as the straw. They are used by the doctors in
hospitals for giving injections.
4. Bicycle pump– it uses two valves, one in the pump (greasy leather) and the other in
the tire. When the handle is pushed in, the pressure inside the barrel becomes
greater than the one in the tire and this pushes air inside. The valve in the tire is
made such that air is locked inside once pumped.avy metal sheets
5. The siphon– it is used to empty tanks which may not be easy to empty by pouring
their contents out. The tubing must be lowered below the base of the tank. The
liquid flows out due to pressure difference caused by the difference in height (h ? g).
Moraa orina answered the question on April 4, 2018 at 18:03
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