Sunlight and Concave Mirror for Cooking

The researchers thought of trying to come up with a makeshift solar cooker in order to test if this way of cooking may be effective and useful in substituting for a frying pan and a stove. The solar cooker may be a possible alternative when cooking outdoors under the heat of the sun. It could also be a huge energy saver and a safer way of cooking, avoiding hazards such as burns. The researchers have picked the safest and easiest procedure and materials in making a solar cooker so that teenagers or even people younger may try making it themselves. The first step in making the solar cooker was finding the right materials. This included a long narrow box, poster board, a roll of foil, Popsicle sticks, cardboard and barbecue sticks. Since the focal point needed to be somewhere in between 5” to 10”, one box was placed on top of another box of the same length and width. Popsicle sticks were taped to the insides of the box as support. The focal point was set and a piece of poster board, measured to fit in the middle of the box was placed there. The foil was then placed on top of the poster board, making sure it was not as furrowed as possible. It was placed in the heat of the sun and there was a certain spot where the light hit.

Two pieces of cardboard were taped to the sides of the spot and the barbecue stick with a whole piece of hotdog was placed where the light hit. The solar cooker with the hotdog was left under the sun’s heat while the researchers watched if it would work. It took about 20-25 minutes before the hotdog was cooked. The researchers then tried to cut another piece of hotdog into smaller pieces to see if it would lessen the time being consumed. It took about 15-20 minutes in cooking the smaller pieces. Lesser time was consumed in cooking the smaller pieces compared to cooking the whole piece. The solar cooker had worked, though after two trials of cooking the hotdog, the foil became a bit greasy due to the oils coming from the hotdog.

The researchers have concluded that the makeshift solar cooker they have come up with works and may indeed be useful when cooking outdoors. It’s inexpensive, overall since the materials used were not pricey and portable because it’s not a hassle bringing it anywhere considering it isn’t bulky and is very light. It’s easy to make with the simplest materials which can be bought mostly from any grocery or supplies store. There are some disadvantages though. This type of solar cooker is time consuming, especially foods such as hotdog or alike. So if you are serving a lot of hungry and impatient people, using the solar cooker are not the best means of cooking. But if by chance the cooking stove at home runs out of gas or breaks down, the solar cooker may be considered an alternative.
Acknowledgement

We would like to thank Mr. Vincent Sabong, our Physics facilitator, for giving us an opportunity to work on an Investigatory Project that enabled us to enhance our skills in the different fields of Science and in preparation for our incoming endeavors. In line with this, we would also like to thank Mikaela Franchesca Pamatmat’s parents for allowing us to develop our Investigatory Project at their house. And above all, we are most grateful to God, the heavenly Father, for blessing us with the proper mindset and for guiding us throughout this project.
Table of Contents

* Abstract
i * Acknowledgement ii * Rationale I * Method/Procedure II * Results and Discussion III * Conclusion IV * Recommendation V * Bibliography (References) VI

I. Rationale
* The researchers arrived at this kind of problem stumbling upon the topic of solar power and how much heat the sun’s rays can produce. * The researchers, as a group think that this is of big significance since global warming is indeed a serious problem in the world, in line with this, usage of energy is one of the factors that concerns this, and as students, investigating on this may be a way of helping out. They also thought that this would be a fun and innovative experience especially since this is not something you see or do every day. * PROBLEM: Can we cook food by using a mirror and sunlight? * HYPOTHESIS:

* H1: If heat is produced once the sun’s rays are reflected through the mirror to the food attempted to be cooked, then we can cook food using a mirror and sunlight. * H2: If the heat coming from the sun is not enough as compared to the heat coming from the gas range or electric stove, then we cannot cook food using only a mirror and sunlight. * OBJECTIVES OF THE STUDY:

* The researchers’ main objective is to be able to come up with a successful investigation and prove that it is indeed possible to cook using merely a mirror and sunlight. Energy shortage is a big issue in our country right now and prices are increasing as the years go by. Conducting this study may also lead to discovering and innovating new ways on how to conserve energy, specifically when it comes to cooking food, since food is one of the things wherein we use our electricity for the most. People use electricity for our microwaves, electric stoves, oven toasters, rice cookers, coffee machines, and so much more. * SIGNIFICANCE OF THE STUDY:

* If by chance their problem is solved and the outcome is a success, it could be of great importance to the school, more so, the community. For the school, the study would help in making students more aware of energy conservation and how they too can help out in reducing their carbon footprint. For the community, this could pave the way to no more energy shortages or brownouts. Everyone, from the upper class to the middle class, and especially the less fortunate can benefit from this. There will be times when the stove will run out of gas or the toaster and microwave won’t work, this can always be an alternative. For those who don’t have this technology or live in developing areas, they can use this as a make-shift cooker. You not only save up, and avoid stress of seeing high payables on your monthly electric bill, but you are able to partake in trying to lessen, if not stop, the effects of global warming.

Review of Related Literature and Studies
* Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun, particularly infrared, visible, and ultraviolet light. On Earth, sunlight is filtered through the Earth’s atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon. * When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, combination of bright light and radiant heat. When it is blocked by the clouds or reflects off of other objects, it is experienced as diffused light. * The spectrum of the Sun’s solar radiation is close to that of a black body with a temperature of about 5,800K. The Sun emits EM radiation across most of the electromagnetic spectrum. Although the Sun produces Gamma rays as a result of the nuclear fusion process, these super high energy photons are converted to lower energy photons before they reach the Sun’s surface and are emitted out into space. As a result, the Sun doesn’t give off any gamma rays.

The Sun does, however, emit X-rays, ultraviolet, visible light, infrared, and even radio waves. When ultraviolet radiation is not absorbed by the atmosphere or other protective coating, it can cause damage to the skin known as sunburn or trigger an adaptive change in human skin pigmentation. * A mirror is an object that reflects light or sound in a way that preserves much of its original quality prior to its contact with the mirror. The most familiar type is the plane mirror, which has a flat surface. Curved mirrors are also commonly used to produce magnified or diminished images or focus light or simply distort the reflected image. Mirrors are commonly used for personal grooming, decoration or architecture. These are also used in scientific apparatus such as telescopes, cameras and industrial machinery. Most mirrors are designed for visible light. However, mirrors designed for other types of waves or other wavelengths of electromagnetic radiation are also used, especially in non-optical instruments. * A sun-deprived village in the Italian Alps has come up with a novel solution to fix certain problems in their community by installing a giant mirror.

The mirror – an eight-by-five meter (26x16ft) sheet of steel – was placed on a nearby peak to reflect sunlight onto their main square below. The computer-operated mirror will now constantly follow the sun’s path. * Does sunlight reflected off a mirror increase the temperature of the sun’s rays? It depends. A standard planar mirror will not increase the energy contained in the rays that reflect off it. In fact, there will be some loss of energy since the reflective surface is not perfect. There is some reduction in the light’s intensity as it passes through the mirror’s glass and reflects off the backing surface. Parabolic mirrors, on the other hand, focus and concentrate the light rays on a single point in front of the mirror, aptly named the focus. Although the energy is not amplified, it will be effectively increased because of the additive effect that will result when the light energy is concentrated.

To clarify, the “rays” of the sun, i.e the photons (energy), do not have any temperature at all, they interact with matter and heat the matter up. * A solar cooker, or solar oven, is a device which uses the energy of sunlight to heat food or drink to cook it or sterilize it. High-tech versions like electric ovens and powered solar cells have some advantages such as being able to work in diffuse light. Because solar cookers do not use fuel and does not cost a thing to operate, many non-profit organizations are promoting their use worldwide to help reduce fuel costs for low-income people, reduce air pollution and slow deforestation and desertification, caused by use of firewood for cooking. Solar cooking is a form of outdoor cooking and is often used in situations where minimal fuel consumption is important, or the danger of accidental fires is high.

II. Method/Procedure
* Select a long narrow box; the longer the box the more heat collection is possible. Choose a focal length between 5” and 10” and design a parabolic curve as seen in the picture. One template could be used for all the cookers. Trace the curve on the open end of the box so that it is centered and straight. * Cut out the curve with a utility knife. Stress the importance of being exact. Measure and cut a piece of poster board that will fix flush against the opening to the box. Attach this with tape beginning at the center and working toward to edges. * Cover the curve with white glue and apply aluminum foil shiny side out. Start in the middle and smooth toward the edges. Try not to wrinkle or fold the foil; you want it as smooth as possible. * Use two scraps of cardboard taped to each side as supports. Using the sun or a projector light, test the focal point. There should be a bright spot where light is concentrated; mark this spot and punch a hole for the skewer. Use a section of a coat hanger from which the paint has been removed for a skewer. * Enjoy your hotdog!

Materials
Materials| Quantity|
Cardboard paper| 1 roll|
Aluminum foil| 1 roll|
Barbecue stick| 1|
Poster board| 1|
Popsicle stick| 2|
Shoe box| 2|
Time Table
Date| Accomplished|
June – July 2012| Planning and coming up with a problem| July 24, 2012| Approval of Problem|
August 01, 2012| Submission of Phase I|
October 6, 2012| Aggregation and Completion of the Solar Cooker;
Experimentation| Budget Item| Quantity| Price|

Cardboard paper| 1 roll| 10 pesos|
Aluminum foil| 1 roll| 20 pesos|
Barbecue stick| 1| 2 pesos per stick|
Poster board| 1 roll| 10 pesos|
Popsicle stick| 2| 5 pesos per stick|
Shoe box| 2| 20 esos|

III. Results and Discussion

| Hotdog cooked whole| Hotdog cooked in smaller pieces|
Under sunlight| 20-25 minutes| 15-20 minutes|
Not under sunlight| It will not be cooked| It will not be cooked|

In using the make-shift solar cooker, the sunlight is the most essential variable needed in making the experiment a success. The light that comes from the sun reflected on the foil of the solar cooker produces the heat for the hotdog to cook. The hotdog cooked as a whole took about 20-25 minutes while when cut into smaller pieces, it took 15-20 minutes.

IV. Conclusion
The researchers have concluded that the makeshift solar cooker they have come up with works and may indeed be useful when cooking outdoors. It is easy to make but at the same time also time consuming. Based on the results and discussion, a whole hotdog cooked under the sunlight will be ready to eat in 20-25 minutes, while a hotdog cut into smaller pieces will be cooked and ready to eat in 15-20 minutes. Hotdogs that are not cooked under the sunlight have no chance of being cooked at all. The light that comes from the sun is the crucial ingredient for the make-shift solar cooker to be able to cook food. It reflects off to the foil of the solar cooker and gives the heat needed to be able to cook food.

V. Recommendation

Food is one of the basic needs of a human being and most food requires cooking with fire. In most households, cooking stoves, microwaves or ovens are often used. But unfortunately there are times when these appliances deem unavailable or defective. Because of this, the researchers thought of another way to cook food in case of unavailability of usual cooking appliances. The researchers recommend the make-shift solar cooker as an alternative way to cook your favorite meals. It can be fast and easy to operate with the help of the light from the sun. Cook and have fun now!

VI. Bibliography (references)

* http://news.bbc.co.uk/2/hi/europe/6189371.stm
* http://wiki.answers.com/Q/Does_sunlight_reflected_off_a_mirror_increase_the_temperature_of_the_sun-rays * http://www.ehow.com/about_5403689_solar-cooker.html