Kategori: English

What Is Floating Where?

There have been some experiments with floating here. I’ll give you one more. Then I have something else up my sleave.

Does everything flow in all kinds of fluids, or is it that some things can flow in water, but not in other liquids?

To try it, you can do the following experiment:

Measure out so it is equal amounts of water, oil and syrup, and pour them into the large jar, one liquid at a time. For the sake of effect, it may have a point to start with water, then oil and lastly the syrup. The liquids will layer.

Now it is time to choose an object and make a hypothesis: ”Will the chosen object float in the oil, in the water or in the syrup?”

MATERIAL
A large glass jar
Cooking oil
Water
Syrup
Various items: grapes, screws, rubber bands, erasers, piece of candle, plastic and metal clips, large sequins, cork, coins, thumbtacks, pearl, nails, magnets …

Orange fireworks

Peel a clementine or an orange. Light a candle and let it burn a little. Take a piece of the peel and squeeze the yellow on the peel against the flame of the heating light.

What can you see? Which fruit creates the most fireworks?

Explanation
It is not only air in an orange peel, but there are also oils in the peel that you use when, for example. makes perfume. When you squeeze the peel against the flame, you release the oils in the shell that are ignited by the flame.

The idea comes from Louise Alfredsson at Nätraby School in Nätraby via www.lektion.se

How much can a magnet carry?

An experiment that contains both science and practical mathematics. Alex counted for 137 nails that stuck to the magnet and could certainly have counted longer if the nails in the box had not run out. Can all magnets hold the same number of things, or does it differ, and if so, why? Something to look into!

If you like, you can start by:

Make your own magnet

Take a magnet and stroke a needle several times (about 20 times needed) after the end of the magnet, but always in the same direction, not back and forth. Try picking up some metal with the needle / needle. Is it working? Then you have made a magnet that turns so that it has the north end towards the magnetic south pole and the south end towards the magnetic north pole.

By pulling the magnet toward the needle, many of the iron atoms in the needle rotate so that their magnetic fields begin to interact. This causes the needle to start acting like a magnet.

How strong is your magnet?

  • What can it pull?
  • How much can it lift?
  • How many train carriages can the magnet hold simultaneously in a long chain, before the chain is broken?
  • Can it make metal objects jump off the table?
  • How high in that case?

Hide the stone – with clues

Stimulate and challenge children in their mathematical development. Work with the mathematical area of ​​locating by having children encounter different concepts and being challenged in formulating and listening to different concepts that indicate location.

Procedure:
• The hider of the stone goes away and finds a good hiding place for the stone. When the stone is hidden, the hider goes to the other participants and gives them a clue, for example that the stone is under something high beside some brown.
• The participants must now observe the surroundings and try to find the stone.
• If more clues are needed, all participants are reassembled and the hider gives more descriptions, for example that the stone is below something high that is brown and green, next to something long and brown, rather than something narrow and green.
• Participants continue to search. When the stone is found, the participant who found the stone may hide it.
As an adult, it is important to support both the hider and the explorer in formulating and interpreting the concepts used.

Make Another Boat

This is an experiment that shows that the shape of an object is important in order to get the object to float in water, but it is also an experiment that can be difficult for children to do themselves, as there are several steps to take into account and many instructions for getting a boat floating. When successful, it is very fun!
Mix all dry ingredients in a bowl, beat over the boiling water. Add the oil and caramel color, and quickly combine the ingredients into a dough. Allow to cool slightly before use!
Give the children a piece of dough and let them shape a boat as they like. Try it in the water and see if it floats. It probably does not, because the shape is so important for the flow properties of the clay (the clay has a higher density than water, and usually sink). In order for the clay to flow, it must be shaped like a coffee cup or a glass, ie as a vessel with high edges.
A further development is to let the children try to build boats of several different types of clay. Is there any mud that floats, no matter how you shape it, or is the shape of the boat equally crucial for all types of clay?

If you need is, here is a recipe on dough:

  • 5 dl flour
  • 5 cups of boiling water
  • 2 dl salt
  • 2 tablespoons citric acid / alum (can also be completely excluded)
  • 1 tablespoon of oil (can also be completely excluded)
  • Food Coloring if you like

Make a Boat

Can a boat be built from anything? And how come boats made of metal can float when metal really drops?
Let the children carpenter, paste, screw and build their boat to their liking and taste, and then let them try the boat in a suitable tub or pool to see if it floats. If it does not flow, you may continue to work with the construction.
Ebba has decided to build a boat using a picture frame she found in the workshop. On it she tapes a piece of paper and then the boat is ready. Sure, Ebba’s boat is floating! Sure the tape dissolves in the water fairly quickly, but the sheer joy of designing is worth taking advantage of.

How long is an apple peel?

The purpose of this activity is to challenge the children in an problem-solving task where there are several different alternatives while also being able to work together, talk and cut with scissors or tear with their fingers. There is also a lot of mathematics, as well as conceptual ability.

How to Do It:

Get an apple and ask: How long is an apple peel?

  • Document the children’s hypotheses, which can be anything from minute to one meter. Some children draw their answer and others show with their hands.
  • Bring out a potato peeler and ask first if they know what it’s called and what you can use it for.
  • Carefully peel the apple around, making the apple peel much longer than the children first think.
  • Measure together how long the apple peel became but first ask what tools we should use to measure it. Relatively soon the children discover that the ruler is difficult to use so it often takes to hands, the cords and after a while we retrieve the tape measure.
  • Get scissors and A4 paper and challenge the children with the question of whether they think they can cut the paper longer than the apple peel.
  • Have the children try different solutions

Friction

First experiment

  • Try spinning a smooth rubber ball in a bowl of water. What happens?
  • Try the same with the tennis ball. What happens to it? Why?

Second experiment:

  • Place two things on a cutting board in wood, for example a button and a eraser. Tilt the board a little.
    What happened? Which object travels fastest? Why?
    Try other things too.
  • Repeat the same experiment with a metal or glass tray.
    What happens? Why?

Wam, Cold or in between?

A little water experiment like this in rainy weather times? Why not?
Vattenskål
For this experiment you will need three bowls, big enough to bring down one or two hands.

Pour hot water in one, cold in another and room-temperatured in the third.

Put one hand in the warm water and the other in the cold. Hold them there for 30 seconds.

Then place both hands in the room-temperatured water. Do your hands feel the same?

Explanation: Human temperature sensation is sensitive to change. For example, when your hand is moved from cold to warm water, the body signals that the water is very hot – even if it is not.

Experiment: To make this study an experiment, try answering any of the questions below. Don’t forget to set a hypothesis and explain the result.

  • What is the shortest time you have to keep your hands in the hot or cold water to achieve this effect?
  • How do you feel if you hold your hands for a long time in the warm and cold water, respectively, before immersing them in the room-temperature water?
  • How fast can you feel the temperature change?
  • What is the smallest temperature difference you can have between the water in the bowls?
  • Does it work if you dip one finger in each bowl only?