Uses and Dangers of Static Electricity

Uses and Dangers of Static Electricity

1. Good uses

   • Paint sprayers use electrostatic charges to get an even coat
     • Bikes and cars are painted in this way
     • Method:
       • 1. The spray gun is charged, this also includes the small drops of paint
         • 2. The paint drops repel the others; this makes them spread out leaving the bike with an even coat
           • 3. The object to be painted will be given an opposite charge to the electrostatic gun, this attracts the negative paint in the gun to give a fine spray of paint
             • You can use electrostatic sprayers in other ways; such as insecticide sprayers
     • Using this method, hardly any paint is wasted in the process which makes it cheaper and in some ways quicker; mainly because you don't have to spend along time trying to get an even coat when the positive and negative charges are doing it for you

2. Disadvantages to Electrostatic charges:

   • When filling up the tank of a car with fuel, it can easily lead to a spark which might cause an explosion. This could occur in fumed places such as when filling a car with petrol in a petrol station
     • This happens when fuel flows out of a pipe and static charge builds up
       • However, if you earth charged objects this would not happen

3. Earthed objects can stop electrostatic charge from building up

   • This can prevent dangerous sparks from occurring, you do this by connecting a charged object to the ground using a conductor
     • You could use a copper wire for instance
       • This provides an easy route for the static charges to travel into the ground; which means no charge can build up and give you a shock
         • The electrons flow down the conductor to the ground if the charge is negative, and up if the charge is negative. Either way, the object will become earthed with a neutral charge
           • Earthing objects such as an aircraft are very important to prevent charge building up in one place so there aren't any sparks which could lead to an explosion