This project grew out of the idea of making a high-performance mini catapult that does not require any type of glue, but is no less resistant.
Teachers may be interested in experimenting with showing students the structural strength of triangles. It will also provide ideas about trajectories and how to convert potential energy into kinetic energy.
You will need:
- 10 wooden craft or popsicle sticks
- 5 strings
- 3 straws
- 1 small plastic container
- 1 rubber band
Steps to follow:
Cut the sorbet into quarters. Squeeze the straw slice and insert the craft toothpick. Repeat this process until you have 3 straws and 3 toothpicks connected end-to-end.
Fold this piece into a triangle and connect the two ends.
Wrap the perimeter of the triangle with tape.
Repeat 2 more times to create a total of 3 triangles. Arrange them in a trapezoidal pattern and add tape around the edges in at least two positions.
Fold the outer triangle up to form a pyramid.
Glue the edges together to keep the pyramid shape intact.
For the arm of the catapult. Lay 5 skewers flat and perfectly aligned. Wrap tape around the kebab in at least two places.
Add a reinforced craft toothpick in the center of your arm. Covers 3 central strings.
Insert the tips of the 3 center strings into the remaining 1/2 straw.
Attach the nail arm to the catapult by attaching a straw to one side of the frame. This creates a flexible joint that allows the catapult arm to move up and down. Attaching the arm to the catapult frame requires a lot of skill. It will be easier if other people help you.
Wrap the rubber band around the arm of the catapult.
Then you pass it through the center of the pyramid and circle it on both sides.
Then you pull it away a lot and let it go over the arm again. You must be careful with this step so as not to break the pyramid.
Place a piece of tape at an angle perpendicular to the upper end of the catapult arm.
Place a small plastic container on the end of the skewer and wrap the tape around its sides. Note that you should leave the tip of the kebab excessive, but cover them with tape so as not to hurt your fingers.
Place one hand on the inside of the pyramid frame and press firmly. Press the end of the catapult arm with the fingertips of the other hand. Pull your arm back, then release it to let your fingers slip off the spikes.