An orange peel is highly porous, meaning that it has lots of tiny holes in it. This seems illogical until you consider the nature of density.Дensity is defined as mass per volume. In fact, what we observe it that peeling an orange makes it sink. It may seem like peeling the orange should allow it to float even better, since by peeling it weвЂ™re removing some of its mass and making it lighter. What happens to the orange now? WhatвЂ™s happening? Place the peeled orange back into the jar. Remove the orange from the jar and peel it.Д¤. It may seem counterintuitive, but in the following experiment weвЂ™ll see that peeling an orange actually makes it sink.ДЈ. It should stand to reason that peeling an orange, and thereby decreasing its mass, should have little or no effect. Objects that are denser than water will sink, while those that are less dense will stay afloat.Д«ecause itвЂ™s less dense than water, an unpeeled orange will float. Density is defined as mass per unit of volume, and objects with a higher mass-to-volume ratio have a higher density. When trying to guess if an object will float, itвЂ™s useful to take into account the objectвЂ™s density. The ice forms a layer across the surface of the lake, but the lake remains liquid underneath, allowing the plant and animal life to survive through the winter. Ice is far less dense than liquid water, so any water that freezes rises to the top. So why doesnвЂ™t a lake freeze solid from the bottom up? The density of water continues to rise until it reaches freezing, but then its density changes again.

In nature, this phenomenon is responsible for a process called вЂњturnover.вЂќ The sinking of cooler water and rising of warmer water causes the layers of a lake to mix, allowing nutrients such as oxygen to be dispersed throughout. It turned green because it touched some of the hot water on the way down, cooling it down and making it sink. The cooled water in our experiment sank to the bottom because it had a higher density than the heated water. As the water cools down, its molecules slow down and come closer together. This makes the space between them increase, resulting in a lower density. When water heats up, its molecules vibrate and move around. WhatвЂ™s happening?Д¬hanging the temperature of water affects its density.

Physics science fair experiment