|
Experiment with Inertia Using a Candle Flame
|
|
|
|
|
|
This Week's Experiment - #230 A Strange Flame
Since I have been "at rest" so much this week, I thought I would do something
on inertia. Inertia is the tendency of an object that is sitting still to
continue to sit still until something pushes or pulls on it hard enough to
start it moving. Once it is moving, it will continue to move, in the same
direction, at the same speed, until something pushes or pulls on it hard
enough to change that movement. Now, there are all sorts of experiments you
can do with inertia, but I wanted to do something that was unusual as well.
For this one, you will need:
a candle
aluminum foil
a plate
a tall, glass container. I used a glass vase, but you could also use a glass
jar or the chimney from an oil lamp.
WARNING: This experiment uses a candle flame. Be sure to get permission,
have an adult around, use common sense and take proper safety precautions.
Cut the candle so that it is at least 4 or 5 inches shorter than the glass
container. Tear off a piece of foil and crumple it around the base of the
candle to form a holder. This will need to be stable enough so that the
candle will not fall over when it is moved. Place the candle in the holder
on the plate and move the plate from side to side to be sure that the candle
is stable enough and won't fall.
Next, light the candle. Let it burn for a few seconds, so that the flame can
stabilize. Then move the plate quickly to one side. Watch the flame as you
move the plate. If you slide the plate to the right, the flame leans to the
left. If you slide the plate to the left, the flame will lean to the right.
Turn the glass container upside down and place it over the candle to form a
cover. Be sure that the flame does not reach near the container. You don't
want it to get hot and crack. If the flame is too close, blow out the candle
and trim it to make it shorter.
Once the flame is the right height, place the container over the candle.
Again, slide the plate quickly to one side. Watch the flame carefully. Wait
a minute! This time, if you slide the plate to the right, the candle flame
leans to the right. Instead of leaning in a direction opposite the movement
of the candle, this time it leans in the same direction as the movement. Try
this a couple of times and then take the cover off of the candle before it
gets too hot.
What is going on? Why does covering the candle with the container make a
difference? Without the cover, the air around the candle was sitting still.
Because of inertia, the air stayed still until the candle pushed it. The
definition of inertia tells us that an object that is sitting still will
continue to stay in one place until something pushes hard enough to make it
begin to move. This resistance of the air to movement bends the flame in the
opposite direction from the movement.
When you put the cover over the flame, the cover pushes on the air to move it
along with the candle. You might expect that the cover would cause the
candle flame to stay upright, just as if you had not moved it. In fact, if
you continue to move it a straight line, at the same speed, it will quickly
return to the upright, just as if it was sitting still. It is only when the
movement of the candle speeds up, slows down, or changes direction that it
will lean. Again, inertia is the cause. Think about being in a car. If it
is sitting still, say at a traffic light, and you suddenly step on the gas,
the car will move forward. What do you feel then? The inertia of your body
resists movement and you feel like you are being pushed backwards into the
seat. The same thing happens to the air inside the container. But wait,
doesn't that mean that the candle flame should lean in the other direction?
The heat of the flame causes the gases in the flame to expand. This means
that they are less dense than the surrounding air. Less density means less
inertia and less force is needed to move it. The denser air around the flame
has more resistance to movement and so it is forced to the side of the
container that is opposite the direction of movement. This pushes the
lighter gases of the flame towards the front, in the direction of movement.
As we have seen in a past experiment, you can observe the same thing with a
helium balloon in a moving car. When you speed up and feel like your body is
being pushed backwards into the seat, the balloon will move forward, just as
the candle flame did.
From Robert Krampf's Science Education Company
PO Box 60982
Jacksonville, FL 32236-0982
904-388-6381
krampf@aol.com
|
|
|
|
Nicholas Academy Index
|
|
Artists, wars, armour, castle games, recipes, geography, quizzes, fashions, pictures of weapons, music, old world maps, women of medieval times, medicine, language, and more.
|
Arabic, German, Japanese, Spanish, French, Italian, Latin, Russian. Games, free software downloads, free online lessons, newspapers, discussion groups, articles, history, culture, quizzes.
|
Play language arts games, improve your vocabulary, create customized puzzles, make your own book! Download free software in the form of shareware, freeware, and demos.
|
Math games, quizzes, fun websites, printable charts, coloring books, tools. Algebra, geometry, fractions, multiplication.
|
Play music games, take free music lessons, explore music theory and history, find great posters.
|
|
Explore animation, filmmaking, build online cities, create and share works of art, write stories, create your own web site, read creativity articles.
|
Science games and quizzes, fun science websites, posters, coloring books, kits, experiments, forensics labs and more.
|
Coloring books, countries of the world, games and quizzes, software downloads, posters, computer jigsaw puzzles, printables.
|
Science can be fun and understandable. Free Experiment of the Week, featuring experiments that are unusual, safe, dramatic, cheap, and fun. From Robert Kramp's Science Education Co.
|
Fun and affordable space items for kids, including toys, games, kits, food products, and more.
|
|
Educational science kits kids will love! Early science kit, DNA explorer kit, robot challenge, forensic lab, volcano kits, crystals.
|
All in one project labs, light kits, sound kits, motion and metal detectors, clap on/off kit, nerve tester and shocker.
|
Civil rights, African American writers, parts of speech, medieval, periodic table of elements, music, astronomy, world maps with flags, literature, poetry, dinosaurs, biology, cats, Japanese anime.
|
Coloring books for kids and adults. Civil war, plants, animals, states, middle ages, cultures, geometric designs, puzzles.
|
Online, via email or through the regular mail. College, accredited high school, free reading and phonics courses, foreign language, history, religion, and more.
|
|
Test your knowledge with these fast, fun, and educational quizzes. Roman numeral addition, world capitals, presidents in order, the elements, world flags, and more.
|
Roman numerals, addition, multiplication, order of statehood, state and world capitals, order of presidents, chemical elements, parts of speech, spanish numbers.
|
Reading systems, loan programs, flashcard, worksheet and test makers, game creators, board games, percentage calculator, puzzle creator, timeline template.
|
SAT, GED, ACT, practice tests, exam preparation. Standardized test practice, content standards listed by state, sample items, scope and sequence, aptitude, essential skills.
|
New and used low cost books and textbooks. Websites with open source books and loan programs.
|
|
Templates, ideas for personal, educational, children's, business sites, design tips and tools, registration and hosting information, step-by-step instructions, quick and easy web page, web building just for kids.
|
Books, posters, videos, software kits, curriculum, courses. Save on teaching supplies, receive free educational materials.
|
This site map lists nearly every page on our site, along with a short description.
|
|
|
|
Educational Poster Store
Hundreds of educational posters in different subject areas. Parts of speech, medieval, solar system, biology, world maps, Einstein, Martin Luther King. Science, math, literature, art, music, english, geography, social studies. If you don't know exactly what you're looking for, this is great to browse for ideas.
|
NASA Website Links
Educational resources include worksheets such as mazes, coloring pages, shuttle model instructions, crossword puzzles, space food tray instructions and grocery list, and more. See the Space Station Sky Watch, view a NASA Astronaut Application or the Space Shuttle Launch Schedule, learn about the U.S. Space Camp and Women in Spaceflight.
|
Zoobooks
Get a free Zoobooks issue and a tiger poster. Zoobooks are the all-in-one, everything-you-wanted-to-know but-didn’t-know-who-to-ask guide to the world’s most fascinating animals, birds, reptiles, and insects. For kids five to twelve.
|
|
