Click on the link below to help you develop your hypothesis.
This research task requires you to perform an investigation (Home Training Tools, 2015).
Objective
To learn about the changing effects of air density.
Materials
FIRE SAFETY: Although this project uses only birthday candles, which even very young children put their faces near when blowing them out on birthday cakes, always exercise extreme caution and utmost common sense when experimenting near an open flame. Make sure there are no flammable liquids nearby, and keep a fire extinguisher or smothering method within reach at all times. Never experiment with fire without adult supervision.
Procedure
Objective
To learn about the changing effects of air density.
Materials
- Aluminum foil (for the basket)
- Birthday candles (for the fuel)
- Scissors
- Ultra-thin garbage bag
- Plastic Straws (for the frame)
- Clear tape
- Lighter
- Adult supervision and common sense
- Plenty of indoor space
- String (if flying your balloon in a space where it can travel beyond your reach)
FIRE SAFETY: Although this project uses only birthday candles, which even very young children put their faces near when blowing them out on birthday cakes, always exercise extreme caution and utmost common sense when experimenting near an open flame. Make sure there are no flammable liquids nearby, and keep a fire extinguisher or smothering method within reach at all times. Never experiment with fire without adult supervision.
Procedure
- Cut a 5cm x 5cm square of aluminum foil. This will be your "basket."
- Use the lighter to melt wax from the bottom end of the candle so it forms a pool about 1cm in from the corner of the aluminum foil.
- Before the wax hardens, press the end of the candle into the melted wax and
hold it in place until the candle stands upright on its own. It may take a few tries. - Repeat with the remaining candles, placing them 1cm in from the other three
corners. Be gentle with the baskets, as too much shaking will dislodge the candles.
If this does happen, simply melt more wax and secure the candle in place again. - Fold the edge of the aluminum foil in 1cm, forming a 'wall' to contain
the wax as it burns, so it won't drip outside the basket. - Measure the width of your bag's opening and determine how long your straw
frame should be. We simply estimated and used trial and error until our frame fit
snugly inside the bag's opening. - If using flexible straws, cut off the bendable part so only the straight section remains.
- You'll need to fasten the straws into two pieces of identical length for the frame. Connecting straws together if needed will work.
- To connect the straws, cut a small slit (about half a cm) at the bottom of one straw then insert another straw into the cut end of the first. The slit will make the connection stronger, but secure it with tape for added rigidity, using as little tape as possible.
- Repeat for the second half of your frame.
- Find the middle of your straws and tape them together in an "X," again using as little tape as possible.
- Place the "X" frame snugly inside the bag's opening. Using as little tape as necessary, secure it in place.
- Staggering the straw frame and the candles (so the candles aren't directly above the straws), tape the basket onto the frame with the candle wicks pointing up into the envelope.
- If you're flying your balloon in an area where it can travel beyond your reach, tie string to the basket, so you can harness it during its flight.
- Take your hot air balloon to an open, mostly empty room to fly it. (You may try it outside, but even days that don't seem windy usually have too much breeze for a balloon like this to fly.) We flew ours in our office lobby.
- Have an adult help you launch the balloon. Have one person hold the closed end of the bag up and away from the basket while the other lights the candles. A lighter with a long stem works best. Continue holding the bag until it fills with air and stands on its own.
- Observe what happens.