Lightning What is Lightning Part of a natural

What is Lightning? Part of a natural process of exchanging electric charges between the

Air currents separate large and small particles of water and ice. These particles

Now, there is a strong attraction between the negative charges in clouds and

There are columns of positive air reaching up from tall objects and even

The air lights and heats up to 33, 000°C since there are so

Lightning Rods Pointed metal rod attached to highest part of building. Thick conductor (usually

How lightning works http: //www. youtube. com/watch? v=Q 3 Awp 3 Cx. SU https:

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Lightning

What is Lightning? Part of a natural process of exchanging electric charges between the atmosphere and the Earth. Electric charges, mostly electrons, are continuously being removed from the Earth’s surface by a variety of processes (for example, evaporation of water molecules).

Air currents separate large and small particles of water and ice. These particles attract different amounts of electric charge. Therefore, different parts of the cloud develop different charges. When thunderclouds form, huge amounts of electric charges tend to concentrate near the bottom of the cloud (for reasons that meteorologists do not completely understand). Strong Positive Region – Water Droplets Strong Negative Region – Ice Crystals

Now, there is a strong attraction between the negative charges in clouds and positive charges on the ground. When lightning begins, a step leader comes from the cloud to the ground. First, it travels for about 50 m, stops for a while, then goes in a different direction, and stops again. Electricity takes the path of least resistance! The process repeats many times, making a zigzag path filled with negative charge (we do NOT see this)! Step Leader

There are columns of positive air reaching up from tall objects and even the ground called streamers. When a step leader and streamer meet, current can now flow through the pathway. This flow of current is called the returning stroke. The returning stroke is much brighter than the step leader, so what we see as lightning is a flow of current which goes from the ground to the cloud! Returning Stroke

The air lights and heats up to 33, 000°C since there are so many electrons crashing through the air so fast and colliding with other molecules. Air molecules colliding with more air molecules as they move around; produce a shock that we hear as “THUNDER”.

Lightning Rods Pointed metal rod attached to highest part of building. Thick conductor (usually copper) connected from the pointed rod to a metal plate (conducts electric charges between the rod and the ground) buried in the ground. Provides a low-resistance pathway for electrical current to flow. If lightning does strike, it directs the charge through the conductor to the ground.

How lightning works http: //www. youtube. com/watch? v=Q 3 Awp 3 Cx. SU https: //www. youtube. com/watch? v=l. C 1 E 8 OM 1 b 3 I (Emerald Robinson) http: //www. youtube. com/watch? v=RLWIBrwe SU 8 (around 2 min)