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## The Effect of Mass on an Arrow's Penetrating Power

Researched by Jorden
1999-2000

PURPOSE

The purpose of this experiment was to determine the effect of arrow mass on its penetrating distance.

I became interested in this idea because I find a bow and arrow fun to use, but I don’t know much about the science behind them, other than how to shoot accurately.

The information gained from this experiment was that a hunting company could make different weight arrows for different competitions or hunting different game so an animal would be killed immediately instead of suffering.

HYPOTHESIS

My hypothesis is that a more massive arrow will penetrate further into the target.

I base this hypothesis on my past knowledge of blowguns and bow and arrows, as well as my reading in books and encyclopedias.

EXPERIMENT DESIGN

The constants in this study were:
The pullback of the bow
The distance from bow to the target
The type of material that the target is made of
The length of the arrow shaft
The fletching of the arrow

The manipulated variable was the mass of the arrow effecting its penetrating power.

The responding variable was which mass would produce greatest penetration into the target.

I’m going to measure the responding variable by, when the arrow is in the target mark a line on the arrow were it comes out of the target. Then pull the arrow out of the target and measure from the point of the arrow to the line to find the amount of penetration.

MATERIALS

 QUANTITY ITEM DESCRIPTION 1 Bow 1 Arrows 5 65 Gram Arrow Tips 5 85 Gram Arrow Tips 5 100 Gram Arrow Tips 5 125 Gram Arrow Tips 1 1 1/2 Foot Thick Cardboard Archery Target 1 Marker 1 Notepad 1 Supporter For Target 1 Archery Stand

PROCEDURES

1. Get out all of your materials and go outside.
2. Be at least 100 yards away from any house or objects that are valuable.  It is best if you cannot see houses.
3. Set up a target 1 - 2 feet thick of high quality cardboard.
4. Measure 50 feet from the front of the target and mark a line where you stop.
5. Set the bow and arrows down behind the line and remeasure the distance from the target.
6. Then pick up the bow and lighter arrow.
7. Put the string on the bow in the slot on the back of the arrow.
8. Set the shaft of the arrow on the arrow rest.
9. Point the bow and arrow into the air and pull the string back to your chin.
10. Aim at the target then release the string and arrow.
11. Set the bow down and get the marker and ruler.
12. Walk up to the target and mark a line on the arrow along the target.
13. Pull the arrow out and measure from the tip to the mark and record the information.
14. Repeat steps 1 ? 12 with the heavier arrow.
15. Repeat steps 1 ? 13 5 times.

RESULTS

The original purpose of this experiment was to determine the effect of arrow mass on its penetrating distance.

The results of the experiment were that the 125-gram arrows penetrated further into the target. It penetrated 142.7 mm on average.

See the table and graph below.

CONCLUSION

My hypothesis was a more massive arrow would penetrate further into the target.

The results indicate that this hypothesis should be accepted.

Because of the results of this experiment, I wonder if deer hunters use heavier or lighter arrows? Or if it effects accuracy of the arrow?

If I were to conduct this project again I would use different arrow masses than previously used. I would also see if the weight effected the accuracy.