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Cool Science Experiments

Chroma Butterflies

Pinwheel Rocket

Hovercraft

Oobleck

Thaumatrope

Hours:
10 a.m. - 5 p.m.
Tuesday - Saturday
Noon - 5 p.m.
Sunday
Closed Mondays

Admission prices

Union Station Members
receive free admission
to Science City. Call the
Membership Office at
816-460-2072 for details.

Discount rates are available for groups of 15 or more. Advance reservations required. Call 816-460-2020 for details.

Parking:
A four-level parking garage is located on the west side of Union Station. Parking is free with a validated ticket from Science City, KC Rail Experience, traveling exhibits, or any of the theaters. Please ask about validation at the ticket counter. For all other visitors, parking is free for the first three hours and then $1 for each additional half hour. Limited short-term parking is also available in front of the building. Please insert cash into the honor boxes.

Chroma Butterflies
Supplies
Coffee filters
Wooden clothespin
Water soluble markers
Coffee can lid filled with water

Directions
  • Use the markers to draw several pea-sized dots on the filter
  • Fold the filter in half three times to form a V shape
  • Dip only the corner of the folded filter into the water and hold it while the water rises
  • Watch the colored dots change into rainbows of color throughout the filter
  • When the filter is completely wet, unfold and hang to dry
  • When dry, pinch the sides in toward the center and slide into clothespin to form a butterfly
Colors are more than what they appear to be. Black is actually made from many colors. If an ink or pigment is water soluble, then water will separate it into the various color components. If an ink is permanent, water will not separate the colors, but alcohol will. The process of color separation is known as chromatography.

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Pinwheel Rocket
Supplies
1 flexible straw
1 pencil with an eraser
1 straight pin
1 round balloon
scissors and tape

Directions
  • Inflate the balloon a couple times to stretch it out
  • Cut the ring end of the balloon off
  • Insert one inch of the long end of the straw into the balloon and tightly tape it on
  • Push the pin through the long end of the straw somewhere between the balloon and the bent part (be careful not to stick your finger)
  • Stick the end of the pin into the eraser end of the pencil
  • Hold the pencil and blow through the straw to inflate the balloon
  • Keeping hold of the pencil, remove your mouth from the straw and let it spin
  • Experiment with the direction of the short end of the straw or the point that the pin sticks through the straw to get a faster spin
The pinwheel rocket works because of Newton's 3rd Law of Motion-for every action there is an equal and opposite reaction. What do you think that means? What is the action here? What is the reaction?

The balloon squeezes the air out of one end of the straw and it blows in one direction (action). The straw and balloon then spin in the opposite direction (reaction). How does the amount of action effect the reaction? What other forces are at work here?

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Hovercraft
Supplies
Used computer CD
Plastic or wooden spool
Round balloon
Tape
Scraps of paper or cardboard
Smooth surface

Directions
  • Line the holes up and attach the spool tightly to the print side of the CD with tape
  • Attach the balloon to the other end of the spool
  • Inflate the balloon from underneath the CD and pinch it so no air escapes
  • Set the hovercraft down on a large, smooth, flat surface and let go of the balloon
  • Experiment with control of the hovercraft. Add paper fins or streamers to direct its movement.
The hovercraft rides a cushion of air that lifts it off the surface, minimizing the friction with the CD and allowing it to move without resistance.

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Oobleck
Supplies
Cornstarch (1 cup)
Water (1/2 cup)
Pie pan
Food coloring

Directions
  • Cover table with trash bags or plastic tablecloth
  • Pour approximately one cup of cornstarch into the pie pan
  • Add small amounts of water (a teaspoon at a time) to the cornstarch until the consistency is similar to glue.
  • Add a couple of drops of food coloring.
  • Explore how the mixture will run through your fingers like a liquid, but when you squeeze it or slap the pan, it will act like a solid.
The Ooblick you made is a colloid, a special type of mixture that has properties of solids and liquids at the same time. Other colloids you may have around the house are mayonnaise and jello.

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Thaumatrope
Supplies
Paper
Scissors
Crayons or markers
Pencils
Tape

Directions
  • Cut out two pieces of paper or cardboard in the same shape
  • On one draw a bird and on the other draw a cage
  • Tape the two pieces to the same end of a pencil with the pictures facing out
  • Twirl the pencil and see the two separate pictures blend into one.
  • See what other pictures you can make using this trick.
The thaumatrope uses an optical illusion to trick your eye into seething that is not there. Persistence of vision occurs when our eyes hold on to an image for a split second. If another image is seen during that time our brains blur them together into one image. This is how a series of still pictures seem to move when you watch a movie or television.

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