Multimedia

Why Do Venomous Animals Live In Warm Climates?

Have you ever wondered why hot places like Australia seem to be crawling with venomous snakes and spiders?

Derek Muller investigates in the video below, you can check out his Youtube channel here, and a great ASELL Schools investigation on Freshwater Species and Ecology here.

Frog Spit

Have you even wondered how a frog catches its prey? How can insects stick to its tongue then fall off once it gets back in the frog’s mouth.

This video explains how with some excellent slow motion video.

If you would like to do an investigation involving adhesives but you don’t have any frog tongues, then click here to find a great ASELL Investigation on adhesives.

Gravity Visualised

Did you know that you can perform a class demonstration showing how massive objects in space bend space-time?

Obtain spandex from the fabric store and attach it to a round frame. Then collect some weights and different sized marbles to show how satellites orbit a heavier object.

You may observe this demonstration being done in the video below, you can see some very interesting questions about gravity explained including;

  • Why do all the planets in our solar system go around the same way?
  • How does the sun, earth, and moon system work?
  • What does it look like when gravity bends space-time?

If you are interested in planetary motion, you can find a great, ‘open inquiry’, ASELL investigation here.

The Page Turner

A ‘Rube Goldberg’ machine is a device designed to do something simple in an over-complicated and over-engineered way. It is normally a chain of smaller machines which link together to form one huge device. The expression is named after American cartoonist and engineer Rube Goldberg (1883– 1970). An example of this is the ‘The Page Turner’, which can be seen below.

You can find a great ASELL investigation where students build there own Rube Goldberg Machine here.

This experiment is a fun and effective way to teach students about different types of mechanical energy. It provides a hands on experience of energy transfer and transformation, varying types of energy and conservation of energy.

Here is another very creative attempt at a Rube Goldberg machine that tells your fortune.

 

 Freezing Bubbles


Bubbles are  formed due to molecules in the soap having one end that is attracted to water (hydrophilic) and the other end repelled by water (hydrophobic). This causes the soap to create a thin film over the water. A bubble is made up of two layers of soap molecules sandwiching a layer of water molecules. The integrity of the bubble is held up due to the surface tension properties of water. Water molecules are attracted to each other. Because of this they hold together to create a shape in the air. This is a sphere because the bubble uses the least amount of energy to contain its shape. A sphere has the smallest surface area in relation to its volume.

Bubbles burst in the air because the thin water layer quickly evaporates. Once enough of the water has gone, the integrity of the bubble collapses and the soap particles shoot off in all different directions. This process can be slowed down when bubbles are formed at colder temperatures because it takes longer for the water to evaporate. It is even possible for the water in bubbles to freeze, making an ice bubble. There are videos of this available on YouTube. 

Click here to see a great ASELL investigation where students experiment to find out how to make the best soap bubble!

Self Pouring Liquid

Polyethylene Oxide (PEO) is a polymer with very long chain molecules that end up tugging on one another when dissolved in water. It can make very interesting visual effects when being poured from one container to another. This can make an exciting class demonstration or you may show students the following video.
Polymers can be used for lots of different things. Click here to find a great ASELL investigation that uses Polymers as an ingredient to make the best soap bubble! Click here to find another ASELL investigation where you will be able to make your own Polymer out of milk!

Check out another type of indestructible polymer below, from the YouTube Channel Veritasium. A great resource for STEM based multimedia.

Thermal Imaging

The footage from a thermal imaging camera shows us a ‘heat map’. The camera records how hot something is, then shows us that information in colours so that we can see it, superimposed over a normal video image (this type of image is called a false colour image). In this case the false colour shown corresponds to the temperature of the objects. As temperature changes from cold -> hot, colour changes from blue -> purple -> red -> orange -> yellow -> white.

You can find a great investigation involving the colour of stars here that is based on this effect.

This video shows a racing car ‘doing donuts’ on the tarmac, taken by a thermal imaging camera. Two main parts of the car glow brightly yellow/white – the tyres and the exhaust. Also notice that the trails of where the tyres have been are clearly visible on the road.

In this video the tyres start off dark blue. When the car takes a bend, the outside tyre changes colour to bright yellow, some yellow is also seen on the inside tyre. As the car comes out into the straight again, the tyres cool and their colour changes back to blue/purple.