electrostatics

Electrostatics

By the end of the lesson you will be able to

understand charging of materials

induced charges

how sparks and flashes happen

working of capacitors

The atom and the electric charge

• Atom is composed of three sub atomic particles

• Electron: Negatively charged

• Proton: positively charged

• neutron: No charge / neutral

Charging materials

• when some dry materials are rubbed against each other electrons move to the material that is being rubbed.

• charge on object depends on the particular pair of materials being used

• Material gets charged with static electricity

• PROTONS are never transferred.

Multiple Choice

An atom loses an electron.  What type of charge does it have now?

• positive
• negative

Multiple Choice

During a physics lab, a plastic strip was rubbed with cotton and became positively charged. The correct explanation for why the plastic strip becomes positively charged is that ...

• the plastic strip acquired extra protons from the cotton.
  
• the plastic strip acquired extra protons from the charging process 
• protons were created as the result of the charging process
  
• the plastic strip lost electrons to the cotton during the charging process 

Mostly charges in an object are equal and balanced, static electricity occurs when the charges become imbalanced.

A material that can become charged with static electricity is an insulator

Multiple Choice

___________________ are materials that ALLOW heat and electricity to move easily through them.

• Conductors

• Insulators

Sparks and flashes

• Air is a poor conductor but if size of charges on the charged surfaces is very high air between them may conduct electricity as a spark

• Molecules in air split to form electrons (-) and ions (+)

• Electrons keep moving and keep splitting more molecules. process is quick and it produces a spark

A charge storing device is called capacitor.