Static electricity & Ionised Air

• what is static electricity ?

  build up of charge on insulators
• why do conducting items not tend to get static electricty?

  because when rubbed together the electrons flow to the item, but move straight back as it flows.
• why can insulating items gain static electricity?

  because when rubbed together transfer caused by friction give one item electrons and they cant flow back.
• what happens if the item keeps gaining electrons?

  a potential difference will form between the item and earthly objects.
• what happens if the Pd is large enough?

  the electrons can jump and this is a spark
• • Electrons move from one item to the other item when rubbed due to friction
  • when the item gains more electrons it will develop a potential difference w/ earthly objects
  • electrons can jump giving a spark to you if you touch the item
• an example of practical- polythene rod and cloth, which one turns positive and which one turns negative?

  polythene rod turns negative as the electrons are being rubbed off the cloth onto it. The cloth is then left with protons.
• Insulating materials that lose electrons for static electricity are positive, and the other is negative, they will be attracted .

  If two objects have the same/like charge, they will repel