They are a teaching aid for showing students how the various planets revolve and rotate. With an Earth/Moon/Sun system model you can answer all these questions by just turning the handle.. 1  Why we have day and night.  What a year is.
1. Static electricity is caused by the build up of electrical charges on the surface of objects, while current electricity is a phenomenon from the flow of electrons along a conductor. 2. When objects are rubbed, a loss and/or gain of electrons occurs, which results in the phenomenon of static electricity.
Positive lightning is less common than negative lightning, and on average makes up less than 5% of all lightning strikes. A Bolt from the blue lightning strike which appears to initiate from the clear, but turbulent sky above the anvil cloud and drive a bolt of plasma through the cloud directly to the ground.