Makdi

How does Lightning Strike Ground?

admin — Wed, 27 Jul 2011 06:15:20 +0000

First does the lightning come from cloud to ground or ground to sky? Well, lightning occurs in three ways:

a) Cloud to cloud

b) Cloud to ground

C) Ground to Cloud

Lightning occurs as negative charge resides under the storm cloud and positive ones above the storm cloud. Sometimes a leader charge moves to the ground creating a cloud to ground lightning. Ground to cloud lightning occurs when the negatively charged ions move upwards and meet the positively charged clouds.

Lightning can be natural lightning or artificial lightning. An artificial lightning is the one which is induced by large structures, buildings or planes or rockets. Most of the artificial lightening moves from ground to cloud and natural lightning from “cloud to cloud” or “cloud to ground.”

Artificial Lightning

Natural Lightning

Power of lightning:

The average peak power output from a single strike of lightning is estimated to be around 1 terawatt i.e 1000000000000 W even though the stroke lasts for only around 30 microseconds. Lightning heats the air in its path to as high as 20000 degree celsius.

How Does a Jet Engine Work?

admin — Tue, 26 Jul 2011 05:35:14 +0000

Jet engines which are mostly fitted on fighter aircraft are made on the principles of Newton’s third law - “Every action has an equal and opposite reaction”. What a Jet engine does is – It sucks the air in through the fan at the front of the engine and later this air is compressed in the compression chamber. This high pressure air is then passes through the combustion chamber where it is ignited by fuel and air mixture. This ignites the high pressurized air sucked in and is made to escape through turbines. These turbines also power the compressor to bring in more air and completes a cycle and forms a loop. As the ignited hot gases passes through the turbines and exits the engine, it provides a trust in the opposite direction based on Newton’s law. The engine also works on the principle of Newton’s second law expressed here as : Force = Mass x Acceleration.

The higher the pressure and thrust created in the jet engine, the more the jet will push itself forward. Therefore, the jets known for travelling at very high speeds have jet engines which produce the maximum trust.