Thursday, April 30, 2015

Instantly Freeze in Space?

Space is very cold, much colder than the coldest measured temperature on Earth by far.  This leads to the misconception that without a proper suit, you will instantly freeze in space.  There are several Hollywood movies that push this misconception as truth by showing scenes of people freezing very quickly in space.  A perfect example of this is the movie Mission to Mars.  Tim Robbins character, in an attempt to save his wife from an impossible rescue attempt, removes his helmet while in space.  His face freezes instantly and he dies.  But does this actually happen?  Not the way shown in the movie.



Don't get me wrong, one is still going to die by removing his/her helmet in space, but not by instantly freezing.  First, your body has its own internal energy we refer to has body heat.  This energy will transfer to the few particles in space, but it will take some time.  What is more likely to kill you is the lack of air.  Due to pressure differences, the air in your lungs will quickly expel and you'll have nothing to inhale.  You may see some blood vessels burst and your eyes are likely to be severely damaged, meaning loss of body heat is the least of your worries.

The point in all of this is that a human being without a protective suit in space will not die instantly.  He/she will still die, but instantly freezing won't happen.

Wednesday, April 29, 2015

Homemade Water Tornado

A few weeks ago my 8 year old had the homework assignment of making a homemade water tornado.  In theory, this is very simple and there are several step by step instructions on the web.  Here's just one of many example sites with instructions:

Make a Tornado in a Bottle

My daughter's instructions from school included food coloring to color the water, but the basic instructions were the same.  We constructed our water tornado and spun the bottle around to get the water rotating.  However, we didn't see a tornado.  The water was too cloudy for us to see to the middle.  Despite this failure we did see something very interesting.  The colored water, due to the dish soap, was very wavy, as seen in the video below.

video


It reminds me of the changing bands and storms in the outer atmosphere of Jupiter.  Maybe it was the red color of the water or the movement of the soapy material, but I immediately linked it to the surface of Jupiter.

This is a perfect example of science in action.  We didn't achieve what we set out to achieve, but by keeping our eyes open we still observed something very cool!

Tuesday, April 28, 2015

Making Slime

For her birthday this year, my 8 year old received a slime making kit, seen below.


The kit comes with all of the necessary materials and equipment to make four different types of slime (glow in the dark, magnetic, changing color, and plain).  We haven't tested all of the types out yet, but we did test the changing color slime. 



This is a neat activity and the cost of the kit was minimal.  I've seen these kits in Target for around $10 - 15.  Given there are enough materials for four separate slime making activities, that's a fairly reasonable cost.  Both of my kids loved it and can't wait to make their next bowl of slime!  You can also search the web for homemade recipes, but if you want all of the materials in one kit, this is an excellent option.  


Monday, April 27, 2015

Return of the Brontosaurus?

As a kid I grew up knowing and loving the Brontosaurus, one of the most commonly known dinosaurs.  I later learned, to my great dismay, that the Brontosaurus was one big misconception!  The first use of Brontosaurs was in 1879 but by 1903 it was realized the Brontosaurus was the same as the Apatosaurus.  Thus the end of the Brontosaurus.  It stuck around in many books and continued to be known as a real dinosaur, leading to the confusion of many when they learned the truth.


Recent studies, however, suggest the Brontosaurus should be resurrected as the fossil record shows differences between it and the Apatosaurus.  


The little kid in me is super excited about this because it means my favorite dinosaur as a kid was indeed a real dinosaur!  A piece of my childhood is restored!!!  :-)

Friday, April 24, 2015

This Blog's History: Blowing Out a Candle Experiment

This Friday in This Blog's History I bring back to you the Blowing Out a Candle Experiment.  We all know how to blow out a candle, but what if something is between you and the candle?  Can you still blow it out?  It depends on the shape of the object blocking the candle.  To see how and why, check out the original post below.

Blowing Out a Candle Experiment

Thursday, April 23, 2015

Does Methane Smell?

We all know that human farts don't smell very good, but what causes the stink?  The common answer is methane, but is that the real answer or just a misconception.  It turns out methane causing the stink of a fart is just a misconception.  Methane itself is an odorless gas and therefore can't be the cause of a smelly fart.  So what is the real cause?


Now that we know methane is an odorless gas, let's ask ourselves if methane is even a component of a common fart.  Is that a misconception too?  In this case it is NOT a misconception.  A human fart has methane as a common component.  The most common components are oxygen, nitrogen, carbon dioxide, hydrogen, and methane.  In fact, 99% of a fart is composed of non-smelly gasses.  It's that 1% that causes everyone to run from the room screaming.  That 1% consists of sulfur compounds.  

I know you've enjoyed reading this post (LOL!) and now you are knowledgeable regarding farts.  Be sure to use this new found knowledge for good in the world.  :-)

Wednesday, April 22, 2015

Newton's Cradle

A Newton's Cradle is a great demonstration piece used to show the effects of conservation of momentum and energy.  If you're not sure what a Newton's Cradle is, trust me, you've seen one and probably not known it was a Newton's Cradle.  They come in various sizes, but all look similar to this:


The idea is to pull one metal sphere away from the others and release.  It bangs into the other four and out the other side flies one sphere.  Pull two spheres out and release and you'll see two spheres fly out the other side.  Pull three out and you'll see three fly.  Same goes for four.  Why?  Conservation of momentum and energy.  If you have one sphere's worth of energy going into the collision, you must also have one sphere's worth of energy going out.  Same goes for two, three, and four spheres.  

Recently I took my 8 year old to a science demonstration show and they brought out a scaled up Newton's Cradle using bowling balls!  Very cool!!!


Newton's Cradle can also be soothing to watch and a could be time killer if you're really bored.  They're also very cheap to purchase.  A quick search on Amazon.com reveals Newton's Cradles for as cheap as $12.



Tuesday, April 21, 2015

Rube Goldberg Machines

Spring is here meaning it's time for Rube Goldberg Machines!  Each spring I have my high school physics students build Rube Goldberg Machines.  I previously posted on this here.  There were many different designs completing different tasks.  Here's one that filled glass of water.



This one raised a flag.


Here's one that starting Cosmos playing on Netflix!


With a Rube Goldberg Machine, your imagination is the only limit.  The goal is to complete a very simple task through a very complicated, multiple step method.  If you're stuck inside on a rainy weekend, consider building a Rube Goldberg Machine.  It will definitely keep you busy and your kids will have fun!



Monday, April 20, 2015

Science Center of Iowa

A few weeks ago I had the opportunity to take my kids to the Science Center of Iowa, located in the state's capital, Des Moines.  This isn't the largest science center I've visited, but it's a good one!


We spent about 2-3 hours here and my kids had a blast.  There's a cool dinosaur exhibit, a space mission exhibit, as well as exhibits with hands on activities for kids.  One of the hands-on activities involved building paper rockets, putting them on air tubes, and launching them!  

In addition, there's an IMAX theater if you're into that kind of thing.  We skipped the IMAX and chose to stick with the exhibits.  

The next time you're driving through Iowa, remember there's a cool Science Center your kids will love.  It's not just corn fields and hogs in Iowa.  There's science too!!!

Friday, April 17, 2015

This Blog's History: Fingernail Growth After Death

Do finger nails really continue to grow after a person dies?  At first glance they appear to, but is that just an illusion?  Find out, but reading the original post on this issue from a month ago.

This Blog's History: Finger Nail Growth After Death

Thursday, April 16, 2015

Greatest Discovery of the Future?

In my opinion, the greatest discovery in my lifetime will be the discovery of life on another planet/moon.  Although I doubt we'll discover intelligent life in my lifetime, I'd bet good money we discover some type of life, such as simple cell organisms in the next decade or two.  We've already found several forms of life living in very difficult conditions, which you can read more about here.

Extreme survival: The toughest life forms on Earth

In addition, we've found extremely strong evidence for large amounts of liquid water on Mars' surface in the past.  Although we've known for some time that liquid water existed on Mars sometime in the past, NASA recently announced that enough water to exceed that of the Arctic Ocean on Earth existed at one time.

NASA Research Suggests Mars Once Had More Water than Earth’s Arctic Ocean

Although no past life on Mars has been found, where there's water, there is the possibility of life.

Mars isn't the only place in our Solar System where liquid water exists or existed.  The moons Europa, Enceladus, and Ganymede most certainly have liquid water underneath their surfaces today.  Many other moons in the Solar System likely have water as well.

Jupiter's Moon Ganymede Has Salty Ocean with More Water Than Earth

On top of that, life may exist in other forms where liquid water doesn't exist.  Saturn's large moon, Titan, has liquid methane and ethane seas/lakes.  Life of some form could exist there.

Cassini Zooms in on Sunny Hydrocarbon Seas and Lakes on Titan

The opportunities for life elsewhere are limitless!  The chances of life on any specific object are very slim, but given the billions and billions and billions of planets and moons in our galaxy (and billions of galaxies) it is all but certain many forms of life exist.  We just have to find that life.

As I said above, it will happen.  We will discover life elsewhere.  I think it will happen in the next two decades, but maybe it will take longer.  I only hope it happens in my lifetime.  If not my lifetime, then the lifetime of my children and grand children.  I want them to experience this just as much as I want to experience it.



Wednesday, April 15, 2015

Melting Ice Experiment

Here's a simple science experiment I tried with my 4 year old that you can also try out with your kids.  We setup a simple experiment to test how quickly ice cubes melt in different types of glasses/containers.  To start, you need a few ice cubes of the same size.  It's important to get ice cubes of the same size as different sized cubes will affect your results.  Then grab a few glasses of different sizes, shapes, and materials.  Put an ice cube in each glass/container and time how long it takes to melt.  Is there a difference?  If so, why might that be?  For example, we placed a cube in a glass and another cube in the same style of glass with foil wrapped around the sides.



The foil acts as a bit of an insulator, preventing energy (heat) from entering the glass and melting the cubes.  The cube inside the foiled glass lasted a couple of minutes longer than the regular glass.  Our next step is to cover the top of the glass with foil.  Does that make a difference?  We'll also place a cube in an insulated travel mug with and without a lid.  

For this experiment I recommend asking your child which glasses/containers to use.  Ask him/her to predict outcomes and then discuss/ask why the prediction came true or didn't come true.  A simple experiment such as this allows kids to see science in action, but also to make predictions and use their critical thinking skills. 




Tuesday, April 14, 2015

Auto-Cleaning a Stove

A couple of weekends ago my wife and I decided to auto clean the interior of our kitchen stove.  Most stoves have an auto clean feature.  You close the door, click the auto clean button, listen to the door lock, and wait 3 hours.  The temperature inside gets so hot that any food residue on the interior walls becomes ash and falls off.  Then after cooling down, the door unlocks and you wipe out the ash. Simple, right?  For us, apparently not!

Neither of us paid any attention to the objects sitting on the ledge of the stove above the control panel.  It becomes hot enough on the stove to melt anything that melts.  The salt and pepper shakers were fine, but we also have several candle jars sitting on the stove.  The small candles melted completely inside, which is okay as they did not produce any mess on the outside.  However, there was a strawberry shortcake stand alone candle sitting on the stove.  The thing completely melted, dripping down the control panel.  Poor strawberry shortcake!  Fortunately we caught it before the wax cooled and hardened, otherwise we'd be scraping for hours!

The best part of this adventure?  Our 4 year old comes in the kitchen later and asks us what we are cooking because the kitchen smells so good...due to all of the melted candles!

Monday, April 13, 2015

Santa, Easter Bunny, and Tooth Fairy Discussion

My 8 year old has figured out the truth of the Easter Bunny, the Tooth Fairy, and Santa Claus.  We knew this moment was coming and although we are proud of her for reaching an age of using critical thinking skills to investigate, it's still a bit sad knowing that she's growing older and there's nothing we can do to stop it.

How did this all come about?  We hid eggs on Easter and afterwards my daughter spoke to my wife telling her she thinks a bunny doesn't come in to our house and hide eggs.  She said she thinks Mommy and Daddy hide the eggs.  I spoke with her too and asked her why she thought this and she said that we put all of the plastic eggs in a bag so she thinks parents put in the candy to reuse the eggs every year.  My wife and I are not going to lie to our daughter, so we confirmed what she thought.

This led to a further discussion on the tooth fairy at which point my daughter says: "I don't think the tooth fairy is real.  Fairies on TV and in books are very small.  The tooth would be the same size as the fairy and a fairy can't carry something that large.  Plus the coins and dollar bills would be larger than the fairy and a fairy just can't carry that much."  Can't argue with that reasoning!

The next logical step in the discussion was Santa Claus.  She freely admitted that Santa doesn't come into houses at night and doesn't have time to visit all kids in just one day.  She said she didn't think Santa was real and thought presents were from Mommy and Daddy.  We asked her why and she gave various good reasons and then asked us if we brought the presents.  At that point we told her the truth.  The only question she had was who dressed up as Santa at Christmas, so we told her.  Her next statement was that she knew Mommy and Daddy hid the Elf on a Shelf.

After this I explained to her that we still do these things (present, eggs, elf on a shelf) because they are fun to do.  Knowing the truth doesn't change the fun we have with it and that's the important thing.

So there you go.  My 8 year old figured this all out on her own.  At no point did we directly tell her UNTIL she asked.  As a scientist I want my daughters to learn to think on their own and that's exactly what my 8 year old did.  For parents who hide eggs, place presents, pick up teeth, etc., I wouldn't directly tell your child the truth until he/she figured it out on their own.  Watching the gears turn in my daughter's head as she told us her reasons was a very proud moment for us, her parents.  Once she directly asked for the truth, there's no way I wasn't giving it to her.  To tell her anything but the truth when she asked would be a straight out lie and I'll never do that to my daughters.

After all of this, we made it clear to our 8 year old to not tell our 4 year old until she figures it out on her own too.  Was my 8 year old upset at figuring out the truth?  Not at all.  In fact, she seemed satisfied and proud of herself for figuring it out.  As I said before, seeing her walk herself through this is a very proud moment for her parents.  On the other hand, it's another step in her maturity, confirming what we already knew, that she's never going to be that little toddler with pudgy cheeks again.  That makes this a bit sad, but knowing she's growing into a wonderful young lady makes up for it.

Friday, April 10, 2015

This Blog's History: Baking Soda Stalactites

In case you missed it a month ago, here's a cool science experiment activity to do with your kids.  It requires several days of patience, but it allows your kids to see slow changes.  The goal is to build stalactites using water, baking soda, and string.  You can check out the full details and procedure by clicking through to the original post.

Baking Soda Stalactites

Thursday, April 9, 2015

Science Lab Journal

Every good scientist knows the importance of a detailed lab journal.  I learned the hard way as a graduate student when I needed to go back several months, but my notes were very poor.  It resulted in several days of repeating work I had already done, leading to a lot of wasted time.  My 8 year old has recently started a science journal to write down a few basics of each science experiment she does.  This was her idea and although she doesn't write down a lot, she likes to draw pictures of the experiment and write down the results.

A lab journal is a great way to introduce kids to real science.  The older your child, the more detailed their journal should be.  Not only should a journal detail the procedure, it should include any data, along with results, and a discussion of results.  Did the results make sense?  Why or why not?  What went wrong?  What went right?  What would you do differently?  How might you tweak the experiment to test something different?

As a scientist and a teacher, I definitely encourage the use of scientific journals in any experiment.




Wednesday, April 8, 2015

Cracking Your Knuckles Bad? Good? Neither?

Is cracking your knuckles bad for your health?  Most of us have likely been told that cracking our knuckles will lead to painful arthritis as we age.  That is incorrect.  There is no evidence at all to support this claim.


The misconception comes from a common sense argument that cracking your knuckles rubs away cartilage, eventually causing arthritis.  However, no medical study has shown this to be true.  In fact, studies show that there are no harmful physical effects to cracking your knuckles.


That doesn't mean you should freely crack your knuckles.  If you are experiencing pain while cracking your knuckles, you should stop and speak with a doctor.  That pain could be another medical issue that needs checking.  In addition, cracking your knuckles is annoying to many people and not considered socially acceptable.  Not that you should automatically conform to social norms, but it's something one should definitely consider when around others.  

Tuesday, April 7, 2015

Science News Magazine

If, as a parent or guardian, you wish to increase your knowledge of science current events, I highly encourage you to check out the Science News magazine published by the Society for Science & the Public.

Science News Magazine

The magazine is published every two weeks and provides short overviews of many different science current events, as well as 2-3 feature articles.  The magazine does a great job explaining current events to a general public audience.


Science News is probably over the head of most elementary aged children, but kids in middle school and certainly high school looking for more science in their lives would enjoy this publication.  I've been a subscriber for 2 years and have loved every issue!  

Monday, April 6, 2015

Air Powered Rocket Launcher

A couple of weeks ago my 7 year old had a snow day at school so we needed something to do to keep us busy.  We set out to build an air powered rocket launcher.  To build the launcher we needed 5 feet of 1/2 inch PVC pipe, a straight connector to connect two pieces of pipe, two T-connectors, two caps to place at the end of a piece of pipe, and an empty two liter bottle of pop.  

I purchased a 5 foot length of 1/2 inch PVC pipe and cut it into 3 12 inch pieces and 3 6 inch pieces, leaving a 6 inch piece leftover.  The PVC pipe can easily be cut with a standard hacksaw.  Here's an image of our supplies.


Now connect 2 12 inch pieces using a straight connector.  If you want, you could leave it as 1 24 inch piece and avoid the connector, but if you want to transport or store you launcher, it's easier to store 12 inch pieces.  Now connect another 12 inch piece using the T-connector and place the 2nd T-connector at the end.  Attach your 6 inch pieces to the ends of the T-connector.  Cap your 6 inch pieces with caps.  Place the last 6 inch piece sticking upward from the middle T-connector.  It should look something like this:


Duct tape the empty two liter bottle to the end, keeping an air tight seal.  Now build the rocket.  Start with rolling a piece of construction paper into a tube, using the PVC pipe as a guide to how wide to make the tube.


Place duct tape over one end of the tube to create an air tight barrier.


Now add fins to your rocket using construction paper.


Next construct a nose cone.


Next place the rocket on the PVC pipe as shown a few images above.  Stomp on the air bottle as hard as possible to force air through the PVC piping to launch the rocket.  Turn the T-connector to launch at various angles.  Our video is below.

video



My kids had a blast launching the rocket over and over and can't wait to take it outside!  Go ahead and experiment with different angles and PVC piping designs to affect launch angles and speeds.  Trust me, your kids will love this!

Friday, April 3, 2015

This Blog's History: Quiet After a Snowfall

Ever wonder why it's so quiet outside after it has recently snowed?  There's a science reason for that!  For This Friday in This Blog's History, I bring back to you this topic, which I originally wrote on a month ago.

Thursday, April 2, 2015

Money Lesson

Hmmm...my wife found this the other day in our 4 year old's room.


I believe it is now time to have a conversation regarding the importance of money!  :-)  She also ripped up a couple of $1 bills, but this $5 bill was the kicker.  

Wednesday, April 1, 2015

Emptying a Bottle Experiment

It may be April Fool's Day, but this science experiment is no joke!  Have you ever tried to empty a bottle of liquid by holding the bottle directly upset down?  Give it a try and observe what happens.  Although the liquid empties relatively quickly, it doesn't empty as quick as it could.  For water to leave the bottle, air must enter.  If the bottle is held upside down, air bubbles must work up through the liquid to get into the bottle.  This slows the liquid pouring out.  By tilting the bottle slightly, there's always a gap between the liquid and the air, allowing the air to more easily enter.  This experiment tries something a bit different.  A bottle will still be held directly vertically, but the bottle will be rotated in a circle instead of remaining stationary.

Which bottle empties first?  The motionless bottle or the bottle being moved in a circle?  I tested this out with my girls the other day and here is our video.

video

Yes, that is a bottle of flavored Smirnoff Ice.  LOL!  

It's a bit tough to see from the video, but the circling bottle empties slightly before the stationary bottle.  Why?  By moving the bottle in a circle, the liquid inside isn't pouring straight out the bottom of the bottle.  It twirls around the edges, leaving a gap in the middle for air to more easily enter.  In this way, it's similar to tipping the bottle slightly when pouring.  

Try it out yourself.  You may find using two liter bottles to be more effective.  I'm not sure, but it's something we may test out in the future.  With more liquid initially in the bottle, there may be a greater time difference at the end.