Meghnath is still awed by learning about the different weapons and their technology. He is itching to build something of his own but one that is simple, harmless, and uses the principles of science. He rummages through his pockets and looks around for material. What he finds inspires him to build a simple missile launcher.
Rubber band-powered catapult
Materials required:
- Icecream/ craft sticks - 5
- Rubber bands - 4-5
- Plastic spoon
- Plastic ball/ pompoms/ paper ball
Step 1: Place three craft sticks one on top of the other and wrap each end with a rubber band.
Step 2: Take the two other sticks and place one on top of the other. This time, secure only one end with a rubber band.
Step 3: Take the sticks from Step 1 and place them between the two open sticks (from Step 2) as far as they can go. Wrap a rubber band around the two pieces to hold them in place.
Step 4: Place the plastic spoon along the top stick, as shown, and secure it in place using the remaining rubber bands.
Step 5: Place a ball on the cup of the spoon. Gently pull it back while holding the base, and let it go. See the ball fly into the air.
Step 6: Explore further by pressing back the spoon to different levels and releasing the ball. See how the ball’s trajectory changes. Set up a target and find the right pressure on the spoon that will help the ball hit it.
The science: The catapult uses the potential energy stored in the rubber band and the crafts sticks. When you stretch the stick and let it go, the stored potential energy is converted to kinetic energy which gets transferred to the ball that is launched into the air.
The author is the founder and CEO of Vaayusastra Aerospace, an IIT-Madras incubated ed-tech startup that offers Air Science workshops for children between five and 14 years.
