Dangerous Sports
•
Which are the most dangerous sports
in a thunderstorm? Can you explain
why?
Surviving Lightning
Lightning is caused when the
charge on the cloud is connected
to Earth – We say the charge is
Earthed. The charge will take
the easiest route. Air is a bad
conductor. Most other materials
are better conductors.
A small current (.05A)
through the heart is
enough to stop it.
Why is a prayer position
the best position to adopt
in a lightning storm?
13 April 2015
4.3 Uses and dangers of static electricity
•Static electricity is used in paint spraying,
electrostatic precipitators (reducing
pollution) and photocopiers.
•It can cause explosions when sparks are
produced.
Are you ever shocked by static electricity?
Can you explain when and where this happens?
A spark from a fuel tanker was thought to have started the Buncefield oil depot
fire in 2005. The explosion was reported to have been heard in the
Netherlands!
Using static electricity
• Electrostatic paint
sprayer.
Metal panels are painted
using charged paint. The
panel is made negative
and the paint positive.
+
-
+
-
Why are they given
opposite charges?
Page 91/92 AQA Additional Science guides. Read the
descriptions of how a smoke precipitator works and a
photocopier. Explain both in your books.
13 April 2015
Dangers of static electricity
• A moving powder or liquid can charge
pipes. This can cause a spark which
might explode the substance.
• Some anaesthetic gases are explosive.
Operating theatres have an antistatic
floor to stop charge building up.
Questions
Why is the rubber hose of a petrol pump made of a conducting
rubber?
Why must a petrol tanker be earthed before delivering fuel?
13 April 2015
4.3 Uses and dangers of static electricity
•Static electricity is used in paint spraying,
electrostatic precipitators (reducing
pollution) and photocopiers.
•It can cause explosions when sparks are
produced.