Understanding Static Electricity and Electrostatic Fields

Understanding Electric Fields

The picture is a Plasma Globe - "like lightning in a bottle" - electric current flows through the gas in the ball (usually a noble/inert gas)

Open Ended

Before we start the main topic, if you have any questions about Static Electricity and/or Static Charge, type your question below

( You have 2 mins)

Open Ended

All objects contain protons and electrons (which are charged particles) in their atoms and yet they are not charged, why is that? Write your answer below (1min)

Electrostatic Fields

Charged objects can affect their surroundings even when they are not in contact. For example, this stream of water bends towards the charged surface of this balloon. Why?

Open Ended

From what we learned in the Static Electricity sessions, why do you think the stream of water is bending towards the charged balloon? Does it matter whether the Balloon or Rod is positively or negatively charged? Write your answer below (2 mins)

What is happening?

• Each water molecule (H₂O) is electrically neutral, but the electrons aren't spread equally between the atoms

• The Hydrogen atoms have a slight positive charge.

• The Oxygen atom has a slight negative charge.

• Water molecules "flip" around to face the charged rod.

Fields around charged objects

• An electric field exists around a charged object, which can exert a non-contact force

• Opposites Attract - Likes Repel

• A charged object can also attract an uncharged object.

• We draw Electric Field Line Diagrams showing the direction that the field flows around a charged object

What is happening in each of these Electric Field Line Diagrams? Can you tell what the charges are in each case? Why?

Now we are going to see how fields can affect the charge on uncharged objects

The Gold Leaf Electrocope

Used to detect and measure the strength of and Electrostatic Charge

Van de Graaf Generators

• Use a moving, nonmetallic belt.

• Accumulate very high charges on a hollow metal globe.

• Used in some types of scientific experiment

Van de Graaf Generators

• Charges become so great that the Air around the globe becomes a conductor.

• Sparks leap to any "earthed" conducting object near enough.

• If you make touch the charged globe with this "earthed" conductor the charge is flows out through this to earth and is lost.

Open Ended

If you have any questions about Electric Fields, type your question below

( You have 2 mins)

What did we learn today?

write 3 sentences