Understanding Franklin's Wheel: A Van de Graaff Experiment

In summary, the conversation discusses the use of a van de graaff for experiments, specifically the "Franklin's wheel" experiment. The main question is why the wheel turns and why it turns counterclockwise. The explanation is that the sharp points create an intense electric field which ionizes nearby air particles, causing them to be repelled and shoot away, creating an "electric wind" that drives the wheel. The direction of the wheel depends on the placement of the points.
  • #1
amirali75
1
0
Hey guys,
I'm new to this forum so I'm sorry if I posted in the wrong thread. So we did these experiments with van de graaff and I almost understood all of them except what seems to be "Franklin's wheel" experiment. I know for one thing that the air near the sharp points are ionized but I don't get why it actually turns and also why counterclockwise?
Any help is appreciated.
 
Physics news on Phys.org
  • #2
The sharp points create an intense local electric field which induces a charge on nearby atoms of air (oxygen, nitrogen etc.) by 'sucking' all the opposite charges away. The charged atoms (now called ions) are repelled by the field and shoot away like the exhaust of a jet engine. (This is called electric wind)
The reaction of that jet is what drives the wheel around.

Which way it turns depends on which way you have the points.
 

Related to Understanding Franklin's Wheel: A Van de Graaff Experiment

1. How does Franklin's Wheel work?

Franklin's Wheel is a demonstration of static electricity and uses the principles of the Van de Graaff generator. The wheel consists of a large metal sphere mounted on an insulating stand, with a rubber belt running around it. The belt is charged by a motor, and as it rubs against the metal sphere, it creates a buildup of static electricity. This causes the wheel to spin and can create sparks or attract small objects, such as pieces of paper.

2. What is the purpose of Franklin's Wheel?

The purpose of Franklin's Wheel is to demonstrate the principles of static electricity and its effects. It is also used to show how the Van de Graaff generator works, which is a device commonly used in research laboratories to generate high voltages for experiments.

3. Can anyone perform the Franklin's Wheel experiment?

Yes, anyone can perform the Franklin's Wheel experiment with proper safety precautions. However, it is recommended to have some basic knowledge of electricity and understand the potential hazards involved. It is also important to follow instructions carefully and use appropriate safety gear, such as gloves and safety goggles, when handling the equipment.

4. What are some safety precautions to keep in mind when using Franklin's Wheel?

Some safety precautions to keep in mind when using Franklin's Wheel include wearing safety gear, such as gloves and safety goggles, to protect against electric shocks. It is also important to keep the experiment away from flammable materials and only use it in a well-ventilated area. Additionally, do not touch the equipment while it is running, and turn off the power before making any adjustments or repairs.

5. Are there any practical applications of Franklin's Wheel?

While Franklin's Wheel is primarily used as a demonstration, it has some practical applications. The principles of static electricity and the Van de Graaff generator are used in various fields, such as particle accelerators, air purifiers, and electrostatic painting. It also has educational value and can inspire curiosity and interest in science and technology.

Similar threads

Measuring Charge on a Van De Graaff Generator: Methods and Obstacles
    • Electromagnetism
Replies
2
Views
2K
Van de graaff without insulation?
    • Classical Physics
Replies
1
Views
3K
Electrical Decided to make a Van De Graaff generator
    • DIY Projects
Replies
8
Views
4K
Troubleshooting a homemade Van de Graaff machine
    • Electrical Engineering
Replies
20
Views
3K
Why is current in Van De Graaff generator so low?
    • Electromagnetism
Replies
14
Views
8K
I Leyden Jars increase spark length?
    • Classical Physics
Replies
9
Views
2K
Small & Lightweight High Voltage Power Sources: Ideas?
    • Sci-Fi Writing and World Building
Replies
25
Views
11K
Let current from a Van de Graff generator flow through you
    • Electromagnetism
Replies
5
Views
3K
How Does Proximity to a Van de Graaff Generator Affect an Insulated Conductor?
    • Introductory Physics Homework Help
Replies
1
Views
981
Van der Graaf Generator: Charge, Potential and Redesign Questions
    • Introductory Physics Homework Help
Replies
8
Views
1K

Hot Threads

Recent Insights

Back
Top