Science “tricks”!

Looking for ideas for challenges or new party piece to show unsuspecting friends? Here are some cool science tricks that you can wow your friends with at home.

Remove a penny from under a match without touching it – or even from a bowl of water without getting your fingers wet!

Raising the matchstick drawbridge

A tricky problem! CC-BY science made simple

A tricky problem! CC-BY science made simple

 

For this science trick you will need an empty match box, three matches and a coin. Set the matches and coin up like the picture so that the coin is trapped beneath the leaning match. Then get your friends to try and remove the coin without touching the matches.

Watch the video below to find out how to raise that match drawbridge and release the coin.

 

 

 

 

 How does it work?

When the two touching match heads ignite the heat makes them fuse together. The top and bottom surface of the leaning match burn at different rates. The top surface is hotter and burns faster causing it the shrink more than the bottom surface. This places the top surface of the match under higher tension than the bottom surface and the match begins to bend.

 

Floating paperclips

Things that are denser than water, like paperclips, sink in water. If you give this a go you will quickly see your paperclips sinking to the bottom of a glass of water.

This video shows you how you can use science to trick those pesky paperclips into floating. Then trick your friends by showing them your successfully floating paperclips and get them to have a go (without telling them how of course!).

 

 

How does it work?

CC-BY-Armin Kübelbeck

CC-BY-Armin Kübelbeck

 

The molecules within a liquid are all attracted to each other by cohesive intermolecular forces. The molecules at the surface of a body of water have no water molecules above them. As a result they are more strongly attracted to the water molecules beside and beneath them. This causes a phenomenon called surface tension.

The surface tension means that the surface layer of water is more resistant to external forces than the water beneath it. By resting the paperclip on tissue paper at the surface of the water you are able use this high surface tension to support the paperclip and stop it from sinking to the bottom of your glass.

 

Parting pepper

Pretend to be Harry Potter and make pepper scoot away from you with the touch of a finger or magic wand.

 

 

How does it work?

The surface tension that allowed us to float paperclips in the previous science trick is also playing an important role here. Surface tension causes the surface of water to dome upwards slightly. This is why you can overfill a glass of water without it spilling.

Detergents like washing up liquid and soap are part of a special chemical family called surfactants. When used in low concentrations these work to reduce the surface tension of water causing the water molecules to relax and spread out. By floating pepper on the surface of the water you are able to see this spreading out effect as the pepper is transported towards the edge of the plate or glass.

 

Still have your floating paperclips?

You can make them sink again by reducing the surface tension in the same way.

 

 

Rising Water

Start this science trick by placing a coin in a dish of water and asking your friends to try and get that coin out without getting we fingers or spilling any water.

When you have finished watching them struggle you can wow them by removing the water using this science trick. You will need a glass, four matches and some Plasticine or blu-tack.

How does it work?

Several things take place during this science trick. Soon after you cover the lit matches with the glass they go out and it is after this that the water is drawn up into the glass. This sequence of events holds the key to the science that is taking place.

When you first cover the matches the fire heats up the air inside the glass and it expands. The glass restricts the amount of available oxygen, needed to keep the matches alight and soon the matches go out. Without the flames there is no heat source and the air starts to cool down and contract. This draws the water from the dish into the glass allowing you to remove the coin without getting wet fingers.

There you have it, science demonstrations you can use to impress your friends and colleagues.
Happy experimenting!
________________________________________________________________

Free water worksheets

             …just sign up for our newsletter

Sign up to our newsletter for all the news on where we are performing, our new shows, the best of our blog, fun activities and our latest special offers.

We are giving away a series of 7 free water worksheets for KS2 and KS3 or simply to have a go at with the kids in your life, when you sign up to our newsletter.

These worksheets contain fun demonstrations, facts and tips on topics such as pressure, surface tension and water saving. Just pop your details in and the sheets will be sent straight to your inbox.

____________________________________________________________________________

sms group shot with props smallWe are science made simple, a social organisation which promotes science, maths and engineering in schools and to the public. You can find out more about what we do, book us live in action with one of our exciting shows, or sign up to our newsletter and find out what we’re up to!
Posted in Activity, Chemistry, Exploring Science, Physics