Category Archives: Blog

How Do Solar Powered Flashlights Work?

By Timothy J. Peters | Submitted On May 24, 2010

Solar power lights are rather ingenious inventions that have many uses. Who would have thought you could use the sun to power a light, or a flashlight? Solar powered flashlights are pretty cool little gadgets. They generally look quite similar to a regular flashlight. They have a simple switch that turns them on and off. They have an area on one end that emits light…sufficient to allow to be used at night or in any dark area.

A solar powered flashlight uses sunlight energy, converted into electrical energy in a solar photovoltaic (PV) cell or panel that sits on the outside of the flashlight, that is then stored in a battery. Most solar powered flashlights use LED or Light Emitting Diode lamps rather than an incandescent light bulb, as LED’s take less electrical current to operate, and they last longer. While an incandescent light lasts, on average, for about 1000 hours, an LED lasts for an average of 100,000 hours.

Similarly, solar charged batteries that are used in the solar powered flashlight, as compared to the normal, single use nickel, lithium, or cadmium batteries generally seen in flashlights, usually will not require replacement for about two years with steady use. The comparison rate is about 15 hours for a regular battery, compared to around 2500 hours for a solar rechargeable battery.

To maximize the usage of your solar charged batteries, you should leave the flashlight on for 15+ hours at least once a month to fully expend the charge. Rechargeable batteries have a memory effect. Therefore if you continually use the flashlight without ever fully discharging it, it will eventually only recharge to a lower (memory) level, and never return to 100 percent of its available power.

For best results, keep your solar powered flashlight on a window sill when it is not in use, where the solar panel is exposed to the maximum amount of sunlight. If you’re not using it regularly, be particularly mindful to turn it on…and leave it on…as described above, at least once a month.

You can find solar powered flashlights in most hardware stores today. They’re great for camping and emergency use. Every vehicle and every home should have one. If you wonder why…think about those times that you’ve needed a flashlight in a hurry only to find that the batteries were dead, and you had no spares…or didn’t know where they were!

Some amazingly innovative designs are being created for solar flashlights…with add-ons like siren, flasher, cell phone charger, etc… in addition to the basic flashlight design. There are also any number of solar flashlight key chains are on the market today. The price range varies, depending on the uniqueness of the style, the outside casing, and additional functions.

If you’re interested in “spreading the light” in a very solar way, you may want to visit bogolight.com. The name stands for “Buy One, Give One.” SunNight Solar, the company that operates the BoGoLight Program is a Limited Liability Company founded by Mark Bent in 2006. Having served in the American Diplomatic Corps in a number of developing countries, Mark saw the need for light in many places, and found a way to provide it. When you purchase one solar flashlight at BoGoLight, or through one of its affiliates, such as InHabitat, an identical solar flashlight will be donated to a non-profit who collects and ships the lights to areas of need throughout the world.

What a unique and wonderful way to “shine a little” light…in a very solar way…and light the dark for those who cannot see. Solar powered lights are the wave of the future.

Timothy Peters is a solar energy enthusiast and author. He lives in Spokane, WA and enjoys teaching others how to save money with solar energy and help the planet through renewable energy. You can visit his site, www.HomeSolarPowerExplained.com [http://www.homesolarpowerexplained.com], to learn more about solar power lights [http://www.homesolarpowerexplained.com/solar-power-lights/] and other solar energy topics.

Article Source: http://EzineArticles.com/expert/Timothy_J._Peters/628049

Peters, T. J. (2010, May 24). How Do Solar Powered Flashlights Work?. Retrieved April 19, 2018, from http://ezinearticles.com/?How-­Do-­Solar-­Powered-­Flashlights-­Work?&id=4352117

pH Meter Design and Working

pH meter is an important tool in chemistry mostly used in pharmaceuticals to determine the acidity or alkalinity of different solutions. It consists of a pH probe that passes electrical signals to the pH meter and displays the pH value of the solution. For accurate measurements, however, pH meters requires proper calibration by dipping it into test solution of known pH and adjusting the meter accordingly. The test solution of known values called buffers. Learn how to calibrate a pH in three ways.

For more exposition on the subject please go through the slide

You can get more information here 

What are a light switch and a dimmer switch?

You can turn On any lights be it at home, in a machine, or vehicle by using the ‘light switch’ but sometimes for some reasons you don’t want the full beam of light therefore, you use the dimmer switch so you can go from high beam to low beam and vice versa. Sometimes the arrangement is three positions, that is, high, low and off. However some applications demand smooth control of light intensity between low and high. In this case intensity is continuously variable using any of different variations and technique used for dimmer. There are different Variations of Dimmer Switch including:

  1. Programmable dimming control via ARDUINO etc.
  2. Some phase shift control by TRIAC
  3. PWM power control
  4. Simple transistor control
  5. Steps Transformer Control
  6. Potentiometer/Rheostat

Where is a dimmer switch useful?

A dimmer will work with incandescent and LED lights, and DC motors; also heating elements such as power control of heating devices like heating element in Water Bath, Incubator, and hot air oven/sterilizers. However there are design variations and complexity but the type of simple control is not smooth but it does work. One good thing about this is that it is durable and sustainable. Precision may not be taken seriously but it is accurate.

Dimmer Switch is used in:

  • Light intensity control for ophthalmic equipment like microscope: ophthalmoscope, slit lamp, bipolar coagulating diathermy etc.
  • Light intensity control for homes and apartment
  • Could be adapted to speed control of small electric motors

How do I make a simple Dimmer switch?

The simplest dimmer switch is a variable resistor also commonly called rheostat. You achieve control by varying the resistance between the light and the power supplies. When a variable resistor is used in a circuit to vary the brightness of a light bulb, you make the resistance greater when you want a dimmer light setting and you make the resistance smaller when you want a brighter light setting. Resistance is increased by increasing the length of the path of resistive material through which the electrons have to flow, and is decreased by decreasing the length of the path. .

Resistance is calculated in an electrical circuit, like the one below, through the use of Ohm’s law, and is measured in the units of ohms.

Source(s):http://www.sciencebuddies.org/science-fa…

Effects of Electricity

Electricity produces many results even though it’s invisible but its effects could be felt. Some of its effects are magnetic, physiological, mechanical, lighting/luminosity, heating etc. and all this effects have significant importance in human life and have applications in science, medicine and industries. Check here for additional info http://www1.curriculum.edu.au/sciencepd/electricity/effects.htm. Meanwhile check the link below for additional information.

What are the effects of Electricity

The Effects of electricity Electricity is form of energy which could not be seen,but its presence could be detected due to numerous effects it has in our daily living. 1. Mechanical effect An electric fan for ventilation through the rotation of its blades; A vacuum cleaner that cleans our floors with dirt’s.These devices operate because of electricity.

 

Voltage, Current, Resistance and Relationship between Them

Electricity is  an invisible form of energy but its presence could be felt and detected due to numerous effects it has in  our daily lives. Electricity has such effects as mechanical, chemical – the  best example for a chemical effect of electricity is Electroplating, thermal – a typical example is a vacuum cleaner that cleans our dirty floors, magnetic, and luminous or light effects. For Students, Technicians and Engineers to manipulate and make effective use of electricity and electronics, we need to understand the basics. The basic of electricity starts from Voltage, Current, Resistance and Ohm’s Law which is the relationship between them. Get more from the link below.

Voltage, Current, Resistance, and Ohm’s Law

When beginning to explore the world of electricity and electronics, it is vital to start by understanding the basics of voltage, current, and resistance. These are the three basic building blocks required to manipulate and utilize electricity. At first, these concepts can be difficult to understand because we cannot “see” them.