Back to 2006 Student Contest Winners List
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Have you ever seen ball lightning, or heard of it? Well if so, you have probably gotten descriptions of, or even seen, small floating balls of fire with very odd behavior. Ball lightning happens during a low humidity thunder storm. Ball lightning can also happen after one of these storms is over. For example, when my mom was the same age as me, ten years old, she saw ball lightning. It happened one day when she was at school. She was in fourth grade, and it was a snowy winter day with an unusual storm going on. Not only was it snowing, but there was thunder and lightning. Suddenly there was a loud “Crack!” and the whole building went pitch black. Next, my mom saw one of the mysterious balls of fire streak past the window. Later she discovered that the tree across the street had been struck by lightning. Although nobody knew exactly what ball lightning was before, an explanation for these mysterious phenomena has finally been found. Two scientists named Eli Jerby and Vladimir Dikhtyar created a ÜMicrowave DrillÝ that accidentally created ball lightning. When the ball lightning was created, the men were testing the capabilities of a drill that used heat instead of a blade. They got a surprise when some molten material dripped off of the drill and became a ball of fire. The drill was made out of a magnetron from a common microwave oven, and a hollow aluminum rod. The magnetron runs a current that’s always switching on and off through a vacuum tube in order to create microwaves. In order to condense 600 watts of energy into 1 cubic centimeter, the rod forms a cone near the end. A regular high-power microwave oven, like the one in my house has a volume of about 40000 cubic centimeters. To find the cubic centimeters, I measured the inside of my microwave and it was 8 inches high by 15.5 inches wide. The length was 18 inches. I needed to know the metric measurements so I converted the inches to centimeters and got 20.32 centimeters by 45.72 centimeters. To do this, I multiplied my amount of inches by 2.54, which is the conversion factor, because there are 2.54 centimeters per inch. 8 inches x 2.54 = 20.32 centimeters To get the total volume of my microwave, I multiplied the height by the width by the length. I got 36576 cm3. Width x Height = Volume Inside the frame of the microwave door, my microwave says that it puts out 12.7 amps. Watts are volts times amps. The voltage in my house is 120 volts. Therefore, my microwave puts out about 1500 watts. Volts x Amps = Watts This is what happened: as they were testing the drill by turning it on and melting holes through different materials, they discovered that some of the molten material hung onto the drill when they pulled it out. On some of the subjects, as the drill was pulled out, the molten material fell off, and then started bouncing and floating around the room. The power density of the experiment that Jerby and Dikhtyar did was almost 14,300 times the power density of a normal microwave oven. How I got the power density was simple: watts divided by volume. They used a 600 watt magnetron and they concentrated it into 1 cubic centimeter. 600 watts divided by one equals 600 watts. Watts/volume = power density Therefore 600 watts was the experiment’s power density. Our microwave was 1524 watts focused into 36576 cm3 1524 watts/ 36576cm3 = 0.042 watts Therefore my microwave’s power density was 0.042 watts and went into 600 14,285.7 times. The power density is important because it explains why the microwave drill can melt materials with very high melting points, and since lightning melts similar materials, and ball lightning occurs near where lightning has struck in nature, ball lightning is created by the amount of heat generated by lightning. One theory suggests that the thing in the lab was ball lightning. The theory is that when lightning strikes the ground, mineral grains are dissolved. Then, the mineral vapor groups together to form a sort of fluff ball of burning silicon that glows because it’s exposed to oxygen, and is light enough to float on the wind. A similar theory is that the mineral vapor creates a much heavier fluff ball which can not float on the wind, but is so hot that its outside layer is plasma, so it floats and glows. So next time you see a cow running away from a floating ball of fire, remember that you’re not seeing a UFO, but a fluff ball of burning silicon.
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