Go Ask Your Father: Static Electricity, Space Deaths, Metallurgy, Seasons

“Day three. Seven black and white photos of your life. No people. No explanation. Challenge someone new each day.”

Thanks, A Momma’s View for the challenge

I don’t know if your weather is acting all wonky, too, but ours is a bit off its rocker. The temps are reaching 20-22 degrees (C) (70-74F). Once upon a time snow suits were worn under Halloween costumes. I’m really hoping this isn’t the calm before the storm. I’m really hoping that winter isn’t going to be as long and cold as summer was long and hot. This week has been the ideal perfect temperature. Sunny. A little breeze. No sign of hurt-your-face-cold. No sign of that four letter bad word s-n-o-w. Though it’s not bad to me, I like s-n-o-w.

1. What’s static electricity and how does it make a balloon stick to the wall?

Static electricity is a great way to study electricity without getting hurt. Mostly. It’s hilarious to watch kids go down a plastic slide and get to the bottom and see their hair standing on end. Or shock each other after jumping on the trampoline in sock feet. It’s even worse in the winter when the air is dryer. Speaking of dryer, we laundry doers have a great time battling static. All those dry clothes rubbing together can make a lightning bolt of it. The easiest way to think of it is as shell. On the shell are electrons and different elements have a different number of electrons. When two object rub against each other, like your butt going down the slide, some electron swapping occurrs. The atoms that have space on their shell take electrons from the other surface that doesn’t have room for more. The thug surface that stole electrons is not negatively charged while the victimized surface that lost electrons is positively charged (it now has more protons than electrons). Thank to your butt you are negatively charged, too, no matter how optomistic you are. Since like charges repel each other (just like magnets) your negatively charged hair stands on end as each strand repels all the others. Mine doesn’t do that. Then you go and touch something that is grounded and you release your negativity and are shocked to feel it happen. What you are feeling is all the electrons moving to the neutrally charged surface. It can be upwards of 25,000 volts! So when you rub a balloon on your head, electrons transfer from your hair to the balloon. Now the balloon is negatively charged and those electrons are attracted to the protons on the wall and the balloon sticks.

2. Has anyone ever died in space?

There have been four space vehicular accidents since 1967 that has killed four cosmonauts (Russian astronauts) and 14 astronauts. The first cosmonaut actually died when his space capsule hit the ground at roughly 150 mph when the capsule’s parachute failed to open upon reentry. On June 30, 1971 3 cosmonauts died after detatching from the space station, Salyut 1. A pressure valve accidently opened and they suffocated. Georgi Dobrovolski, Viktor Patsayev, and Vladislav Volkov are the only three to have ever died in space (above 62 miles). In January of 1986 seven astronauts died when the Challenger space shuttle exploded 73 seconds after lift-off. A faulty O-ring caused a fuel leakage and the demise of a great crew, among them, teacher Christa McAuliffe. In 2003 seven more astronauts died upon reentry when damage to teh thermal protection system caused structural damage and the shuttle broke apart over Texas and Louisanna. Many more have given their lives during training and testing. Without any of them we would not be where are today as we explore the cosmos.

3. How do you build metal? With wood or something?

Poor Bang is slightly confused on the production of metal. No wood goes into the making of any metal. Copper was first discovered around 9000 BC. Since then many alloys (metal mixtures like tin and copper to make bronze) have been created. To make metal you first need to mine it. Vast amounts of rock and dirt need to be excavated to collect the ore (raw metal, like bread is raw toast). Excavating is relatively the same for all metals. Refining and producing specific metals requires different processes. To make copper an added chemical binds to the copper and is then submerged in water. Air is pumped in from the bottom and the coated copper clings to the bubbles and rises to the surface. Then it’s put in a smelter and gets melted at 2,000 degrees. Not your normal oven temperature. Silica is added and any iron in the ore mixes with it and rises to the surface and is skimmed off, leaving the copper at the bottom. Simply put, this copper mixture is only 95% pure, still impure enough to leave deformities. An electric current is run through it copper is deposited on cathodes while the impurities (gold, silver, selenium, and tellurium) form a slime on the bottom and are process separately to be recovered. This is very simplified. To learn more visit your friendly, local blacksmith. Thanks to 12,000 years of science we have metal for everything.

4. Why do we have seasons?

So we don’t have too much summer or too much winter.

Just kidding. You didn’t believe me, did you?

This answer is easy compared to making metal. The Earth is tilted at a 23.5 degree angle. So instead of spinning perfectly upright it spins more like this thing…

But it’s not the spin of the Earth that gives us the seasons. That rotation gives us night and day. The tilt of the axis changes the angle of the sun’s rays as the Earth travels through its orbit around the sun. When the northern axis points toward the sun, the northern hemisphere experiences baseball, beach days, and long hot, days. When the southern end points to the sun the north gets football, skiing, and long, cold nights. The southern hemisphere gets the exact opposite. I still can’t comprehend Christmas being in the summer time. Y’all down there are weird. I’m surprised you haven’t fallen off the Earth yet, being upside down all the time.

Photovoltaic Geeks

More sunlight hits the Earth in one day than every person on Earth could use in 27 years!

~Bill Nye

Today’s lesson is on Photovoltaic cell. Or for us normal people, solar cells.

I’m sure you’ve all seen them. Or at least a picture of them. Like these…

solar panels

They provide electricity at no cost. No fuel required. There are zero emissions, zero pollution, zero noise. So how do they work?

First, you already know electricity is the movement of electrons – those negatively charged particles of an atom. When they move, we get zapped.

Second, silicon is a metalloid  which means it’s sort of a metal. So it can sort of conduct electricity.

A solar panel is basically a silicon sandwich- negative and positive silicon (like peanut butter and jelly). Where they meet is where the action is. The trading of electrons could be described as some peanut butter getting in the jelly and some jelly getting in the peanut butter.

There’s a whole lot of science involved and I’m trying not to get too pvtechnical. But, to simplify it as much as I can; the negatively charged electrons join with the positively electrons in the middle of the sandwich. Sunlight then causes them split up again. When the panel is connected to a circuit the divided electrons flow through the circuit and meet up again in the “sandwich” and start the process all over.

When many panels are joined, you get an array, like the one shown in the first picture. These arrays can be used to power everything electrical in houses. If this house creates more electricity than it uses, that electricity is sent back to the power company. In many areas, power companies are required by law to pay the user for any electricity that is returned to them.

Most solar panels are only 11-15% efficient. This means that only 11-15% of the sunlight that hits the panel is converted into electricity. While this may sound low, it’s more than efficient for a few rooftop panels to create enough electricity for the house to be self sufficient.

Now let me entertain you. The reason for this science lesson is because Crash already got one, sort of. I haven’t really explained this all to him because I, myself, just learned it as I was typing this. Hence, I’m no expert.

Anyway, Crash received a solar power kit for Christmas. This thing can be built into 14 different robots and they all move of their own accord under the power of direct sunlight.

The first thing he wanted built was a car. But first we had to assemble the motor box (that’s the box under the solar panel “head”). It wasn’t easy because those parts were small. After we completed the motor we were supposed to test it. Unfortunately, it snowed for five days, so it sat for a while. We played in the snow in the meantime.

Anyway, when we had a sunny morning we opened the front door and direct sunlight beamed in. We grabbed the car and set it up and IT WENT BACKWARDS!

Crash and Bang laughed at that. I did too. I thought I put gears or the motor or something in backwards. Confused, I switched the positive and negative wires. Guess what? That made it run forwards. I seriously had no idea switching the wires would cause it run in the opposite direction. But now that I know how solar panels work, it makes sense. Those electrons are going to flow, unlike a battery, in the same direction (hence it’s called direct current). Switching the wires simply changes the direction of the flow.

Anyway, Crash and Bang played with it until the sun didn’t shine through the door anymore. And Bang was getting a kick out of cast a shadow on the panel to make the car stop.

We’re certainly not setting any land speed records here, but we are learning!