1. Charging by Contact – Friction

2. Charging by Friction: the transfer of electrons between two different neutral objects when they are rubbed together charging by friction video

3. Charging by Contact – Friction Charging by Friction: the transfer of electrons between two different neutral objects when they are rubbed together -materials hold on to electrons with varying strengths

4. Charging by Contact – Friction Charging by Friction: the transfer of electrons between two different neutral objects when they are rubbed together -materials hold on to electrons with varying strengths How do we know which one will lose electrons and which one will gain electrons?

5. Charging by Contact – Friction Charging by Friction: the transfer of electrons between two different neutral objects when they are rubbed together Electrostatic Series: a list of materials arranged in order of their tendency to gain electrons

6. Electrostatic Series: a short list tendency to relative attract electronscharge highrubbernegative polyethylene ebonite silk fur wool glass lowacetatepositive

7. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive tendency to relative attract electronscharge highrubbernegative polyethylene ebonite silk fur wool glass lowacetatepositive

8. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive tendency to relative attract electronscharge highrubbernegative polyethylene ebonite silk fur wool glass lowacetatepositive e.g. ebonite rubbed with fur

9. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive tendency to relative attract electronscharge highrubbernegative polyethylene ebonite silk fur wool glass lowacetatepositive e.g. ebonite rubbed with fur -ebonite becomes negative because it is further up on the series

10. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive Try these:a) rubber rubbed with silk b) wool rubbed on glass c) polyethylene rubbed with glass

11. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive Try these:a) rubber rubbed with silk rubber = negative silk = positive b) wool rubbed on glass c) polyethylene rubbed with glass

12. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive Try these:a) rubber rubbed with silk rubber = negative silk = positive b) wool rubbed on glass wool = negative glass = positive c) polyethylene rubbed with glass

13. Using the electrostatic series: look up the two materials being rubbed together. The one higher on the series will become negative, the other will become positive Try these:a) rubber rubbed with silk rubber = negative silk = positive b) wool rubbed on glass wool = negative glass = positive c) polyethylene rubbed with glass polyethylene = negative glass = positive

14. Charging by Contact – Friction e.g. wool rubbed with glass Before rubbingAfter rubbing wool glass neutral 5+3+ 5-3-

15. Charging by Contact – Friction e.g. wool rubbed with glass Before rubbingAfter rubbing wool glasswool glass neutralneutralnegativepositive 5+3+5+3+ 5-3-7-1-

16. Charging by Contact – Friction try this one:ebonite rubbed with fur

17. Charging by Contact – Friction try this one: ebonite rubbed with fur Before rubbingAfter rubbing furebonite neutral 5+3+ 5-3-

18. Charging by Contact – Friction try this one: ebonite rubbed with fur Before rubbingAfter rubbing furebonitefurebonite neutralneutralpositivenegative 5+3+5+3+ 5-3-3-5-