Simply Science: Experiment Time
By Shani Asokan Ceylon Today Features
Science doesn’t have to be difficult. It can be simple, fun and a great stay at home activity! Here are some simple experiments you can do with a few materials you have lying around the house.
While these experiments are safe to do at home, we recommend getting an adult to help you. Besides, this is fun for the whole family. Get ready to see science in action!
Did you know that you can poke holes in a bag full of water and not spill a single drop? Let’s learn how and why this is possible.
What you will need:
- A pencil sharpener
- A plastic bag (ziploc or similar)
- A large bowl
- Create your leak-proof bag
First, sharpen your pencils. Make sure the tips are nice and pointed. Be careful not to hurt yourself!
Fill the bag half-full with water and seal it closed. This will allow you to grip the bag better.
Now, its time to test the theory of the leak-proof bag. Hold the bag over your bowl to avoid any spills or messes (just in case!). Carefully push one of the pencils right through one side of the water filled bag, just until it pierces and comes out of the other side. Do this with a few more pencils and watch the magic happen!
How it works
The bag you have used (ziploc or any similar bag) is likely made from low-density polyethylene (LDPE). It is one of the most widely used packaging materials in the world. It is lightweight, durable and very flexible.
The LDPE bag is made up of polythene molecules. Think of these like they are strands of cooked spaghetti. Very flexible and easy to move around, but also stick together easily. When you push the pencil through the bag, the polythene molecules come together to create a temporary seal around the pencil, so all the water stays inside the bag. This seal will only last while the pencil in the hole you have created. Once you remove the pencil, the hole remains because the polythene molecules have been stretched permanently.
Tip: Pencils that are smooth and cylindrical work better than pencils that have ridges or harsh edges because these make it more difficult for the seal to form around the pencil.