Currently, burning fossil fuels is the main source of energy here and around the world.  Those fuels emitting greenhouse gasses are considered by most associated scientific organizations in the world as contributing to a potential global catastrophe in the making.  With this, we are critically dependent on electricity for almost every necessity we have in our standard of living. 

When a feather or a plastic bag or almost anything light is placed in water, these items will generally float.  This is easy to understand if you think of water being more dense than the other item.  If you put something heavier in water, it tends to sink like a rock or a piece of metal but this doesn't fully explain how an iron ship can float. 

The two heaviest naturally occurring radioactive elements (by atomic weight) on the earth are Uranium and Thorium.  Uranium is used as a fuel in modern commercial nuclear power reactors for electricity generation.  A lesser known fact is that thorium could also be used as a nuclear fuel .  Naturally occurring thorium is not fissile and so not able to undergo nuclear fission (separation) and as such it takes an initial nuclear reaction to enable this process.

A very popular urban myth is that window glass is a liquid.  This apparently originated by the recognition that old European cathedrals had windows with the glass being thicker at the bottom than the top.  The actual cause of this is not attributable to gravity pulling the glass downward in a slump but rather the early window manufacturing techniques followed by a common practice of mounting window glass with the thicker side down.