Purpose: The purpose of this lab was to build a catapult or any type of launcher on our own that would launch a marshmallow at a certain length by using a specific type of force that would allow the marshmallow to achieve reaching its final target.
Materials:
12 Dowel Sticks
Multiple Rubber Bands (all different sizes and thicknesses)
A plastic egg head
Marshmallows
Procedure:
How to build the launcher:
We used rubber bands and connected 4 dowel rods to make a base
We placed a dowel rod across the middle of the base connected by rubber bands
Then, we added 1 vertical rod to each corner with a horizontal rod at the top connecting the vertical rods.
We added another dowel rod to the shooting arm to make it longer and added a long, stretchy rubber band to give tension to the shooting arm.
Finally, we added a cup at the end of the shooting arm and shot our marshmallow.
Error/Procedure 2:
When we shot that catapult, the stick was blocking the way for the shooting arm, which was needed to stabilize the entire catapult.
It did not shoot therefore, we had to rebuild.
In our second procedure, we used all the same materials but we rebuilt the structure.
We had the idea to make a more simple structure connecting two dowels together 6x to make it stronger.
For the base, we put 3 pairs of dowel rods horizontally next to each other with spaces in between.
We connected the 3 pairs together by one pair of dowel rods that went across all of them.
Then we put 2 rods vertically upward connected to the sides of the base and connected together at the top, in the shape of a triangle.
We placed a rubber band across the vertical rods with a plastic cup in the middle and shot successfully
Calculations: Average: Distance= 13.6 meters Time = 1.4 Seconds D=RT -13.6= Vi(1.4) -13.6/1.4 = 9.7m/s Horizontal component = 9.7 m/s Vf= Vi + at -Vf= 0+ (-9.8)(0.7) = 6.86 m/s down Vertical Component = 6.86 m/s down -9.71^2+6.86^2= 11.88 m/s Initial Launch Velocity= 11.88 m/s Angle= tan inverse (6.86/9.7) -Angle= 35.24 degrees
Observations:
Data Table:
Conclusion: During this marshmallow lab, we were able to learn from our mistakes through trial and error. After making a catapult that did not work as we thought it would, we decided to rethink and rebuild the catapult using the same materials to construct a new structure. We built a triangle-shaped structure that had a stretchy rubber band connected through the middle. The rubber band created the force as you pull it back with the marshmallow. We concluded that the farther back we pull the rubber band, the farther the marshmallow will ascend in the air.