Electrostatics/Static Electricity

• Electrostatics is the study of static electricity
• Static electricity is a stationary electric charge usually generated by friction
• It causes sparks or attraction between the charged particles
• For example if a comb or plastic ruler is rubbed on a sleeve or on dry air
• It becomes charged and can pick up tiny scraps of paper or cause hair to stand on its end
• Nylon and other synthetic clothes crackle and sparkle when they are removed
• The sparks are better observed in a dark room
• Lightning is an example of static electrical discharge
• Electrical charge is because of:
• Either the presence of extra electrons resulting in a negative charge
• Or the absence of electrons resulting in a positive charge
• If electrons are removed from atoms a certain material e.g. glass then the material gains a positive charge
• Glass/Perspex gains a positive charge if it is rubbed using a silk cloth
• Electrons are removed from the atoms of glass and transferred to silk
• When polythene (polythene) is rubbed with a woolen cloth
• electrons are transferred to the polythene and it thus gains a negative charge
• Unlike charges attract i.e. they are drawn to each other
• This is similar to magnetic forces where opposite poles attract
• Like charges repel each other
• i.e two negatively charged items or positively charged items repel each other

To access more topics go to the Combined Science Notes page.