Effect of Wind Load on a Building

 PURPOSE

The purpose of this experiment was to determine the effect of height to width ratio on the wind load of a building.

I became interested in this idea when I was watching a news report about a hurricane that made some taller buildings fall down while sparing many shorter buildings. People paid lots of money and did extra work to fix them.

The information gained from this experiment could help architects determine how to design buildings of a certain size so the wind has less drag on it. People could get hurt if the wind has too much drag and makes the building fall down.

HYPOTHESIS

My hypothesis was that as the height to width ratio increased, the wind load (drag) would increase.

I based my hypothesis on an article from World Book Encyclopedia that was called “Wind Surface.” It said, “That wind can blow so lightly that you can’t even feel it or it can blow so hard that it rips trees out of the ground and can crush buildings.”    

EXPERIMENT DESIGN

The constants in this study were:

•    The speed of the wind.

•    The size of the wind tunnel. 

•    The time I gave the wind to blow on the structure.

•    The type of material I used to make the structure (plywood). 

•    The surface area of the shape facing the wind. 

•    The shape facing the wind.

•    The unit I used to measure with.

•    The strength of the wind.

•    The size of the wheels.

•    The material the wheels are made of.

•    The number of wheels on each structure.

•    The size of the axels.

•    The number of axels.

•    The material the axels are made of.

•    The size of the axel holes in the wheels.

•    The place where the wind comes out of.

•    The machine the wind comes out of.

•    The size of holes the axels go in the structure.

•    The type of glue I used to glue the structure together.

•    The placing of the structure in the wind tunnel.

The manipulated variable was the height to width ratio of the structures.

The responding variable was the force of drag.

To measure the responding variable, I used a spring scale.  

 MATERIALS

QUANTITY	ITEM DESCRIPTION
1	Stopwatch
1	73cm by 73cm Wind Tunnel
16	Wheels
2	Leaf Blowers
16	Axel pegs
1 piece of	30cm by 121cm Plywood Board
1	Electric Wood Saw
1 Bottle	Wood Glue
1 Can	Spray Paint
1 Box	Small Nails
1	Clamp
1	Carpenters Pencil
1	Ruler
1	Hammer

PROCEDURES

1)    Build Structures  

A.    Buy a plywood board that is 30in by 121in.

B.    Cut four pieces of board so they are 5 inches by 4 inches then glue and nail the boards together so that one of the faces of the board has an area of 20 inches2.

C.    Put your 16 wheels on the 16 axle pegs. 

D.    Drill a hole in the board that is big enough for the axle peg to go in but small enough so that the peg doesn’t come out easily. Put wood glue around the axle peg’s end so that it will stay inside the hole.

E.    Clamp down on two sides with your clamp.

F.    Screw a metal hook into the front of the structure.

G.    Cut twelve more pieces of wood that have four 4 by 5, four 2 by10, and four10 by 2. Repeat step one with all. 

2)    Move wind tunnel if needed.

A.    If you need to take wind tunnel into a quiet room with no people in it but you and a supervisor. 

III)    Start your experiment.

A.    Put your structures in the wind tunnel one at a time and let the wind blow on them for two minuets every ten seconds write down how many newtons are pushing on the structure.

B.    After you do this for six times with every structure go to each amount of time being a multiple of thirty except zero and find the average newtons of each structure in the multiples of thirty going to one-hundred-twenty.

RESULTS

The original purpose of this experiment was to determine the effect of height to width ratio on the wind load of a building.

The results of the experiment when my structure had a surface of about 20 inches2 having wind blow on my structures for 10 minuets and me recording how many newtons were pulling on the spring scale on my first structure at

CONCLUSION

My hypothesis was that as the height to width ratio increased, the wind load (drag) would increase.

The results indicate that this hypothesis should be rejected because my results were mixed. My hypothesis said that when the height to width ratio increased so would the wind drag. On my first two structures that was correct. On my last two however it was the exact opposite of that. On my last two structures it was the smaller the height to width ratio the more drag the building had on the wind.  

After thinking about the results of this experiment, I wonder if it matters with other objects such as a car or a plane. 

If I were to conduct this project again I would do the experiment with more trials than I had this. 

Researched by ------ Ben M

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Candle Wax Hardness on the Burning Time of a Candle

 PURPOSE

The purpose of this experiment was to find the effect of candle wax hardness on the burning time of a candle.

I became interested in this idea when I observed a candle in my home and wondered what made it burn for such a long time. I also thought there might be ways to make it burn even longer.

The information gained from this experiment could help candle makers produce longer burning candles. Decorative candles are expensive, so users would want them to last as long as possible. Also people need candles in case of a power outage. They need candles they can rely on to burn as long as the outage lasts.

HYPOTHESIS

My hypothesis was the more hardener that was put in the wax the longer the candle would burn.

EXPERIMENT DESIGN

The constants in this study were:

•    The size of the candle made 

•    The lighting device

•    The place where each candle is kept

•    The air movement in the room during testing

•    The air temperature

•    Method for making the candles

The manipulated variable was the hardness of candle wax. 

The responding variable was the amount of time each candle burned.  

To measure the responding variable, I used a stopwatch to determine how long each candle burned.

  

MATERIALS

QUANTITY	ITEM DESCRIPTION
1	Block of paraffin wax
1	Hardener
1	Pot
1	Pencil or Pen
2	Pieces of Paper
1	Stop Watch
1	Glass 2 cup measuring cup
24	tea light containers
24	votive wicks with metal stop tabs
1	measuring scale (triple beam balance)
1	coffee can
1	wax melting thermometer
1	wooden stir stick
1	deep sided cookie sheet with tin-foil liner
4	tin foil cups

PROCEDURES

 I.    Get materials

1)    Block of paraffin wax.

2)    Hardener

3)    An old pot to melt wax in (the wax will ruin this pot!)

4)    A pencil, paper, and a stopwatch

II.    Make the candles

1)    Break 3-4 large pieces of wax and melt in a boiling water bath.

2)    Treat with hardener

a.    Measure hardener in grams using a triple beam balance.

b.    Add 4.5g. of hardener to 250ml. of melted wax and name this batch “1x”. 

3)    Form first batch into candles

a.    Make 5-10 candles in the molds.

b.    Label this batch as in step 2.

4)    Repeat steps 2-3 except add 9g. of hardener and label this batch “2x”

5)    Repeat steps 2-3 except add 18g. of hardener and label this batch “3x”

6)    Repeat steps 2-3 except add 36g. of hardener and label this batch “4x”

7)    Repeat steps 2-3 except add 0g. of hardener and label this batch “control”

III.    Starting the Experiment

1)    When the wax cools take the wick and cut it to the preferred size (1cm. above the candle wax)

2)    Then get out the pencil and paper and be ready to record

3)    Find the stopwatch and set it so that it will record time

4)    Separate the groups so that all candles are about three centimeters apart

5)    Next light the candles and start the stopwatch

6)    When any given candle stops burning write down the time it stopped and which hardener group it was in

RESULTS

The original purpose of this experiment was to find the effect of candle wax hardness on the burning time of a candle.

The results of the experiment were that the control group had an average burn time was 150.8 minutes. The group with 4.5 grams of hardener had an average burn time of 155.7 minutes. The group with 9 grams of hardener had an average burn time of 173.8 minutes. The group with 18 grams of hardener had an average of 182.3 minutes, and the group with 32 grams of hardener had an average of 182.7 minutes. 

CONCLUSION

My original hypothesis was the harder the wax the slower the candle would burn. 

The results indicate that this hypothesis should be accepted, because as shown in the graph, the candles with the more hardener burned longer than the ones with little or no hardener. It did appear that there was very little additional effect above 18 grams of hardener, however.

After thinking about the results of this experiment, I wonder if the candles’ burn time would be affected by different types of waxes instead of different amounts of hardener. I could test beeswax vs. paraffin, paraffin vs. soy wax, or paraffin vs. gel candles.

 I feel a little uncomfortable knowing that I had some outliers in my experiment. If I were to conduct this project again I would replicate my experiment except that I would make more batches of candles for each hardener amount. Although I was careful this time I would be more careful with watching the time the wax was melted, the volume of paraffin in the candle molds, the wick placement, and the air movement during the burning time. 

Researched by ------- Jordan K

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Water Acid Levels on the Growth of Radishes

PURPOSE

The purpose of this experiment was to determine the effect of water acid levels (pH) on the growth of radishes. 

I became interested in this idea when I found an article in the newspaper on how acid rain affected a country and ruined their crops. 

The information gained from this experiment could help society to understand ways that acid rain affects plants. This could act as a warning to people and prevent future problems. 

HYPOTHESIS

My first hypothesis was that the radishes watered with a pH level of 3.0 would be most negatively affected.

My second hypothesis was that the radishes watered with a pH level of 6.0 would be least negatively affected.

I based my hypothesis on the fact that the lower the pH level, the higher the acid level. Acid rain is most severe when the acid level is highest and the pH is lowest.

EXPERIMENT DESIGN

The constants in this study were: 

•    The amount of soil in each container

•    The type of soil used in each container

•    The amount of water received

•    The amount of light received

•    The date planted

•    The type of radish, cherry belle

•    Growing temperature 

•    The date on the seed packet

The manipulated variable was the pH level of the water.

The responding variable was the radish growth.

To measure the responding variable at the end of my experiment, I pulled all of the radishes out of the soil, took off the excess soil, and weighed all of the radishes in the same pH group at the same time, and then I divided the weight by the number of radishes to find the average weight of a radish. 

MATERIALS

QUANTITY	ITEM DESCRIPTION
2	60-watt light bulbs
1	package potting soil
2	light fixtures
2	Planting trays containing 72 cubicles
1	syringe
1	Package of radish seeds
1	roll of masking tape
5	milliliters of water

PROCEDURES

1.    Gather all materials

2.    Make sure that the room temperature is at least 23.9 degrees Celsius

3.    Place potting soil in each of the 72 individual containers until full

4.    Place one radish seed in each container

5.    Pour enough soil to cover each radish seed

6.    Place lights 30 cm above the radish seed containers so that each radish seed gets the same amount of light.

7.    Water soil until fully soaked, then allow to drain

8.    Repeat step 7 on day 3

9.    Measure the sprouting radishes

10.    When the radishes reach a height of one centimeter use the masking tape to mark which containers get which PH level of water

11.    Water each container with 5 milliliters of water with their marked acid level, do this every three days

12.    Let the radish seeds grow for four weeks 

13.    Pull all of the radishes out of the soil, take off the excess soil, and weigh all of the radishes in the same pH group at the same time 

14.    Find the average for each radish by dividing the total weight of the radishes by the number of radishes in that category.

15.    Record and compare the averages to find which plants were affected most by the water

RESULTS

The original purpose of this experiment was to determine the effect of water acid levels on the growth of radishes. 

The results of the experiment were, pH 3 had an average of .044 grams, pH 4 had an average of .047 grams, pH 5 had an average of .052grams, and pH had an average of .068 grams. Therefore the lower the pH level the more the radishes were affected.

 CONCLUSION

My first hypothesis was that the radishes watered with a ph level of 3 would be most negatively affected.

The results indicate that this hypothesis should be accepted because the average weight for the pH 3 group was .044 grams which was less than that of the other pH levels averages.

My second hypothesis was that the radishes watered with a PH level of 6.0 would be least negatively affected.

The results indicate that this hypothesis should be accepted because the average for this group was .068 grams which was higher than the other pH averages.

After thinking about the results of this experiment, I wonder if there could be a way to prevent the effects of acid rain on plants, or to prevent acid rain altogether.

If I were to conduct this project again I would have paid more attention to the amount of water being given, I would have done this project outside in the summer, and I would have had more radishes per group.

Researched by ------ Erika B

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