Electrostatics in Our Lives Lesson 6 December 7th, 2011

Making Use of Static Charges By using static charges in technology, we are able to make devices that improve our lives. For the following technologies answer the following questions. Why do you think this technology was created? How does this technology improve our daily lives? How does this technology work? Draw a diagram to explain how it works.

Jig Saw This activity will be done using a method known as the Jig Saw Method. There will be several groups formed. Each person in the group will be given a technology to read over and really think about how it works.

“Expert groups” will then be formed for each topic “Expert groups” will then be formed for each topic. In these groups you will talk about the technology and answer the questions given to you. You a now considered an expert Each expert will then return to their original group to explain to the others how it works. At this time members of the group should ask questions that may not have been addressed when the expert was explaining the technology.

Electrostatic Paint Sprayers (page 470) 1. Why was this technology created? Conventional spray painting methods leads to overspray in the air and on other objects. This waste of paint costs money and creates messes. Some paint solvents are harmful to the environment and humans and reduced usage would be beneficial.

Electrostatic Paint Sprayers (page 470) 2. How does this technology improve our daily lives? It minimizes wasted paint It ensures an even coat of paint leaving a smoother finish It makes it easier to paint curved objects.

Electrostatic Paint Sprayers (page 470) 3. How does the technology work? The paint leaving the nozzle is given a charge. The object being sprayed receives the opposite charge. The charged paint particles are attracted to the object which results in a smooth layer of paint.

Electrostatic Paint Sprayers (page 470) 4. Draw a diagram to explain how it works.

Electrostatic Dusters (page 475) 1. Why was this technology created? Dust collects on surfaces causing them to become dirty. Wiping the dust with a plain cloth does not capture all of the dust.

Electrostatic Dusters (page 475) 2. How does this technology improve our daily lives? It captures dust faster and easier than other methods. It cuts down on airborne dust which can affect people with allergies.

Electrostatic Dusters (page 475) 3. How does the technology work? The duster builds up a charge by the friction created when the duster is wiped on the surface of the object. The charged duster attracts the neutral dust off of the object and it sticks to the duster.

Electrostatic Dusters (page 475) + + Electrostatic Dusters (page 475) 4. Draw a diagram to explain how it works. + Dust

Electrostatic Precipitators (page 476) 1. Why was this technology created? Most of the world’s electronic energy is generated by burning coal, oil and natural gas. This releases particles into the air that can pose health risks and environmental damage.

Electrostatic Precipitators (page 476) 2. How does this technology improve our daily lives? It removes the dangerous particles from the air The precipitators require very little energy to run and remove 99% of the smoke stack emissions.

Electrostatic Precipitators (page 476) 3. How does the technology work? Smoke passes through negatively charged plates, the particles become negatively charged through conduction. The charged particles then pass positively charged plates which attract the negatively particle. The particles then fall onto collection plates.

Electrostatic Precipitators (page 476) 4. Draw a diagram to explain how it works.

Laser Printer (page 481) 1. Why was this technology created? Inkjet printers are slow, expensive to run and the use of ink can lead to problems like smearing, drying time, and if not used frequently the ink can dry out.

Laser Printer (page 481) 2. How does this technology improve our daily lives? Laser printers are faster than ink jets while providing more precise printing and cost per printed page.

Laser Printer (page 481) 3. How does the technology work? A positively charged drum has the image drawn on it with a laser. The areas touched by light become negatively charged. Positively charged toner particles are attracted to the negative areas on the drum. The drum rolls across paper with a higher negative charge, leaving the toner on the paper. The paper and toner is then run through a fuser where it is heated to melt the toner to the paper.

Laser Printer (page 481) Draw a diagram to explain how it works

Electrostatic Lifting Apparatus (page 488) 1. Why was this technology created? Footprints at crime scenes can be difficult to see.

Electrostatic Lifting Apparatus (page 488) 2. How does this technology improve our daily lives? It allows crime scene investigators to identify a person’s shoe tread left behind at a crime scene.

Electrostatic Lifting Apparatus (page 488) 3. How does the technology work? Foil is placed over the footprint. The foil is electrostaticly charged, this attracts dirt and dust from the footprint. The footprint is now visible.

Electrostatic Lifting Apparatus (page 488) 4. Draw a diagram to explain how it works.

Electrostatic Speakers (page 488)

Electrostatic Speakers (page 488) 1. Why was this technology created? Large speakers can be heavy, take up large spaces and require large wattages.

Electrostatic Speakers (page 488) 2. How does this technology improve our daily lives? The speakers are lightweight and extremely thin making them suitable for many applications that a dynamic loudspeaker would not be suitable for.

Electrostatic Speakers (page 488) 3. How does the technology work? The speaker has three thin layers, the outer layers are porous and the middle one known as the diagram is flexible and vibrates to produce sound. The middle layer is given a permanent positive charge. The audio transformer than creates opposite charges on the two outer layers. This results in the middle layer moving, the charges in the outer layers are repeatedly changed causing the middle layer to vibrate back and forth.

Electrostatic Speakers (page 488) 4. Draw a diagram to explain how it works.