Simple Machines: Catapults
Before Thanksgiving we made catapults using craft sticks, rubber bands and a plastic spoon. Below are some videos on other ways to make levers and catapults with supplies you may have at home.
Below is the video we watched in class:
Two more catapult ideas using popsicle sticks:
If you do not have craft sticks at home. You could make a catapult with a paper tube, rubber bands and a spoon:
There are so many fun activities you can do with a popsicle stick catapult! You may come up with your own ideas, but here are some to get you started: (source)
Attack the Castle:
Build a castle or building with some household objects like cups, blocks or even Legos (without snapping the pieces together). Use the catapult to launch balls at the castle! Just make sure the blocks are not too heavy so that the balls have enough force to knock them over.
Go the Distance:
Make multiple catapults and see who can launch the ball the farthest!
This one is difficult, but fun at the same time! Place a bunch of cups on the floor. Catapult the balls at the cups and see how many balls land in the cups!
Switch It Up:
Try different objects to Do heavier objects go farther? How about flatter objects? You can even try chucking a slime ball (provided it’s not too sticky) at the wall or glass door and watch the slime ball go “splat!”
The following blogs had great ideas:
The Science Behind the Popsicle Stick Catapult
The biggest benefit of STEM projects is that you can show your kids the science visually, which helps them understand the concepts. That’s how I learned physics at school!
You probably heard of Newton’s Three Law of Motion (source):
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
When an external force acts on a body, it produces an acceleration (change in velocity) of the body in the direction of the force.
Every action has an equal and opposite reaction.
You can explain to your child how without touching the catapult, nothing happens. The ball is not going to launch itself without you applying force.
When you pull back the spoon and let go, you overcome the ball’s inertia and fling the ball into the air. The force of the spoon exerted on the ball produces acceleration upward and makes the ball fly into the air. The action of letting go of the spoon causes the reaction of the ball getting launched.
You can also explain to your kid that because of gravity and air friction, the ball was pulled down to the ground instead of flying in the air forever. Then when the ball hits the ground, it bounced and rolled until the friction of the floor eventually stopped it.
If you have preschoolers, Newton’s laws may be a little complicated for their minds. However, you can always try to explain everything in simple terms and start introducing the concept of force and motion to them. You never know what they absorb and remember!