1. Static Electricity

2. Lesson Objective At the end of the lesson, students should be able to:
State that there are positive and negative charges and that charges is measured in coulombs
State that unlike charges attract and like charges repel
Describe an electric field as a region in which an electric charge experiences a force
Draw the electric field of an isolated point charge and recall that the direction of the field lines gives the direction of the force acting on a positive test charge
Draw electric field pattern between two isolated point charges

3. What’s Static Electricity
Static Electricity Safety Video - Fire Explosion shown

4. Electrostatics Two types of electric charge Positive (+) Negative (-)
SI unit for electric charge is coulomb (C)
Law of charges
Like charges repel and unlike charges attract

5. Laws of Electrostatics
When the charges are close  force is strong
When the charges are further apart  forces are weak

6. Examples

7. Electrostatic Fun with Science Bob

8. Electric Field – isolated charges
An electric field is a region which an electric charge experiences a force
Electric field line is the path a positive charge would take if it is free to move
Direction of electric field lines gives direction of force acting on a positive test charge

9. Electric Field – isolated charges
Positive Charge
Negative Charge
Arrows are pointing towards the charge
Field lines are close, nearer to the point
Arrows are pointing away from the charge
Field lines are close, nearer to the point

10. Electric Field – between 2 charges
To sketch combined electric field, the following rules must be applied:
Lines must begin on positive charges and end on negative charges
Number of lines drawn leaving positive charge or ending on negative charge is proportional to magnitude of charge
No 2 field lines can cross each other

11. Electric Field – isolated charges
The number of field lines is proportional to the charge
The greater the charge  the greater the number of field lines

12. Electric Field – between 2 charges
Electric lines of forces are closer to each other in a stronger electric field

13. Electric Field
Electric field between parallel oppositely-charged plates is uniform at the central region