Experimental method and phenomenon: tap several holes (more than two) at different heights of plastic beverage bottle with awl, and fill the bottle with water. The deeper the observation hole, the farther the water is ejected, as shown in Figure A. 。

Method 2: Equipment: balloons, pins and water.

Experimental method, phenomenon: Fill the balloon with water, and pierce several eyes (more than two) at different depths of the balloon with a pin. The deeper the observation eye, the farther the water will be ejected.

Method 3: Equipment: plastic beverage bottle, scissors, thread, balloon and water.

Experimental method and phenomenon: cut the bottom of plastic beverage with scissors, then cut out a rubber film slightly larger than the bottle mouth of plastic beverage bottle with balloon and put it on the bottle mouth, and tie it tightly with thread to make the bottle mouth rotate downward, and the protrusion of rubber film will increase with the increase of water depth. Alternatively, the bottle mouth of the above device can be pressed down into the water, and it will be observed that the deeper it is pressed into the water, the greater the depression of the rubber film, as shown in Figure B. 。