Counterintuitive Demonstration- Ciment rice

Today we are going to see a weird demonstration. Not a weird "weird" demonstration, but let's say it defies logic, with this experiment we want to show that, in order to think science, we need to clear our mind from some preconceived ideas. This is a real problem, often we do not place certain questions because we are sure of the answers, and this is bad science.

NOTE: This demonstration needs adult supervision.

What we need:

• rice,
• a plastic jar, we used a baby's bottle,
• a knife,
• resistant surface, like a kitchen counter,
• patience and a broom.

How to:

1. Fill the jar with rice;
2. Plunge the knife "halfway" into the rice a few times; it's easier if you lean the jar 5 or 6º;
3. Fill the jar again, repeat the process;
4. With a fast and clean hit, jab the knife up to the hilt into the rice, be careful with your hands, an adult must supervise this step;
5. Pull the knife straight up.

What happens?
The jar comes up with the knife.

Why?
The force of pressure can overcome the force of gravity.
The preliminary stabs made rice grains to settle in close to each other. Thousands of rice grains surrounded the knife when we plunged it halfway, after each stab, the grains got closer and closer.
In the last step we pulled the knife straight up into the settled in rice, the knife is sharp enough to be jabbed into this network of pressure, but at same time the rice settles back in from all sides to hold the knife in place.

Please Note:
It's normal if you have to repeat several times the steps above until you have success. Persistence is the key; you may try to change the knife or the container.

This demonstration can be an experiment, or a science fair project:

1. Change the container, different volume, high...;
2. Change the knife width, length, or material....;
3. Change the rice; use other grains, sugar, salt, sesame seeds, sand...

Note:
Record the weights of the containers with and without rice, record the width / length of the knife and all the variables of your essay.

Et Voilá!
Unbelievable!

Enjoy!

Resources:
Connolly, Sean, "The book of totally irresponsible science", 2008

Cleanning pennies

A penny is a penny, but we can make them shiny and clean with a little help of chemistry. This is another demonstration using vinegar.

NOTE: Don’t use this method to clean collection coins, this can damage the coin. If you have collector coins or valuable items ask a specialist how to clean them.

What we need:

• pennies,
• vinegar,
• salt,
• a jar, with lid
• tablespoon,
• paper napkin.

How to:

1. Mix 2inches of vinegar with 1 tablespoon of salt in the flask;
2. Close the flask;
3. Stir to dissolve the salt;
4. Open the flask and place 2 or 3 coins inside;
5. Close it again;
6. Wait 1 or 2 minutes;
7. Open and remove the coins, be careful with vinegar smell;
8. Place the coins in the paper napkin to dry;

What happens?
The coins become clean and shiny
Why?
The solution we made with the salt and the vinegar released the residues of the coins, and the coins become clean as new.
This residue is copper oxide, this oxide reacts with the vinegar (acetic acid) and the reaction product remains suspended on vinegar.

Et Voilá!
Clean as new
 
Enjoy!

Instant facts- Just add water 15

United Nations have 193 Nations, US recognize only 195 countries, but in fact there are 196 countries that meet "requirements of independent country or state status".
in http://geography.about.com/cs/countries/a/numbercountries.htm

Instant facts- Just add water 14

East Timor became the first new sovereign state of the 21st century on May 20, 2002.
in wikipedia

Instant facts- Just add water 13

The common abbreviation for Christmas to Xmas is derived from the Greek alphabet. X is letter Chi, which is the first letter of Christ's name in the Greek alphabet.
in: www.santas.net

DIY Pendant with beach stones

Another DIY project for the Summer.
Use your restless beach stone collection to make beautiful and personalized pendants. You can use them with chain-keys, necklaces or bracelets. You also can paint some lucky charms like the "Evil Eye"- in last picture-, this amulet will protect everyone who use it against the evil eye .
Or you can simply ask your restless to paint the stones as he wishes.

We will need:

• alcohol,
• little stones from the beach,
• thin wire,
• pliers,
• pencil,
• acrylic paints,
• varnish.

How to:

1. Chose your stone, to paint evil eye the stone must be small, round and plain. try to chose the small ones, you will not want to use heavy weight around your neck;
2. Clean the stone with tap water and alcohol to clean the salt, the sand and any other residue;
3. Draw on the stone what you want to paint;
4. Next paint all the stone with a light color, (white if possible);
5. Next color your draw with the other colors, first the light ones;
6. You must resist painting the details, Those will be the last thing to paint;
7. Wait for 4h, paint must dry;
8. Varnish and wait another 4h;
9. Now you have 2 choices:
1. Use the wire and make a cage for the stone: Use the pliers and curl the wire around the stone. The stone must be trapped but not "glued" to the cage. When you finish make a double ring and super glue the 2 turns of the ring.
2. Make a double ring with the wire: Make a double ring with the pliers but don’t cut the ends, super glue the end tips to back of the stone.
10. You can use this in many was: in a bracelet, in a necklace, in key chains...

NOTE THIS:  If you chose to paint the evil eye- in the image-you must know that some people believe that a blue looking towards to us brings bad luck (although the blue-eyed person is good and virtuous), that’s the reason the most common color in evil eyes is the blue (they take away the bad luck)

Et voilá!
Another great use for beach stones

Enjoy!

DIY Christmas Project - EVA Santa Claus ornaments

This week the invited super restless mind is Quiane with a Santa Claus mold. Use it to do some ornaments to your Christmas tree, use EVA or Felt.

Source: Pais Natal para a árvore- em Feltro ou em EVA.






Et Voilá!

Enjoy!