Hot Air Balloons

We wanted to find out how hot air balloons work and if we could make one ourselves. We know that hot air rises and is less dense than cold air, so we searched for some ideas.
This clip showed us how to make a hot air balloon so we basically followed what they did (on a shoe-string budget though!!)

We tried to lift a plastic bag with a hair drier on Wednesday afternoon, but it wouldn't rise. After some thinking, we realised that the classroom was too warm -- so we tried the same thing the following morning when the temperature was cooler. The bag lifting off was a real success.

Next step was to make a large tube that was light enough to lift off the ground. We used very thin computer paper, fine bamboo, tape, and balloons.
A little decoration was added but not too much as paint would have weighed our hot air contraptions down.

Then down to the hall Friday morning to experiment.
Success! They lifted off the ground. The hair drier gave enough wind to lift them off the ground. A bot too much heat though so one balloon popped. (Interesting thing about that though was that the popping balloon caused the paper to rip - the force of the air was that strong!)
Check out the photos!

More Amazing things about Air!

Another experiment to do with 'Air' that we tried was to see if molecules of air could stop paper from getting wet.

What we needed:

Small Glass

A screwed up ball of paper

Glass bowl filled with water

What we did: Put the paper in the bottom of the glass then turned the glass upside down over the bowl and lowered it in to the water. We then lifted the cup straight up out of the bowl and took the paper out.

What happened and why?

The paper remained dry because when the glass was pushed in to the water, the molecules of air did not escape. Instead, they were pressed together and acted as a shield between the water and the paper. 

Pretty cool -  huh?!

Air Force

We are looking at "Air" at the moment. It's amazing what this important, but invisible force can do!
Today we saw how air stops water from entering a bottle.
This is what we used:
A funnel
Small bottle
Plasticine
Glass of water

What we did:
Put the funnel in the bottle and made a small long worm out of the plasticine and fitted this around the bottle neck - making the funnel seal completely and the bottle airtight. We then slowly poured a small amount of water into the bottle - until glass of water was empty.

What happened and how come?
A little water went in to the bottle but as we poured, less entered. Finally, the funnel was full and no water entered the bottle. This was because the air molecules in the closed bottle started pressing together and taking up what space there was- and so stopped any more water from entering.

Try this at home the next time you refill the Tomato Sauce bottle!

How Does Air Change In Different Temperatures?

 2 Science experiments this afternoon!! With all the water bottles in use for Athletics Day we were able to do this experiment as well! The results were amazing with this one- and this experiment was a lot easier for us to do.

Does Air Change In Different Temperatures?

You need:

2 plastic bottles

2 containers wider than the bottles

2 balloons

2 rubber bands

What to do:

1.      Place 2 deflated balloons over the tops of the 2 bottles. (We used red and blue balloons to help identify temperature)

2.      Use rubber bands to secure the balloons in lace.

3.      Place the balloons in the wide containers.

4.      Fill one container with ice cubes. (For the blue balloon bottle)

5.      Carefully fill the other with hot water (For the red balloon bottle)

6.      What do you observe?

When air gets warm, it expands. That inflates the balloon. Cool air contracts, causing the other bottle to shrink.
In this case, the blue balloon not only contracted, it went all the way inside the bottle!

How Does Hot Air Rise Up Through Cold Air?

Here's an experiment we tried to see how hot air rises up through cold air. We used water as it follows the same principles.

We needed:

 Small glass

·        Jug

·        Hot and cold water

·        Food colouring

·        Glad wrap

·        Rubber band

·        Large clear bowl

·        Skewer

What we did:

1.     Use the jug to fill a glass with hot water.

2.     Add some food colouring to help you see the water moving more easily

3.     Cover the glass with glad wrap.

4.     Secure it with a rubber band. Put the glass in the large bowl

5.     Fill the bowl with cold water until the water level is well above the glass.

6.     Poke a hole in the glad wrap with the skewer.

7.     

We watched what happened to the coloured water. It was interesting how it sat on the top of the cold water.

This experiment shows how convection works. Warm water rises through cold water, just as hot air rises through cold air.

Weather Stations - Weather vanes

Next in our creation of weather stations comes a weather vane. These show the direction that wind comes from. We used some cardboard, a square piece of card (for the directions), a skewer, a felt pen cap, tape, and a compass to set these up.






Ollie's Weather Vane showed a strong northerly outside today.      

Cloud in a Bottle

What you need::

clear plastic softdrink bottle

matches

water

What to do:

Fill the bottle one-third full of warm water and place the cap on. As warm water evaporates, it adds water vapour to the air inside the bottle. This is the first ingredient to make a cloud.

Squeeze and release the bottle and observe what happens. You’ll notice that nothing happens. Why? The squeeze represents the warming that occurs in the atmosphere. The release represents the cooling that occurs in the atmosphere. If the inside of the bottle becomes cover with condensation or water droplets, just shake the bottle to get rid of them.

Take the cap off the bottle. Carefully light a match and hold the match near the opening of the bottle.

Then drop the match in the bottle and quickly put on the cap, trapping the smoke inside. Dust, smoke or other particles in the air is the second ingredient to make a cloud.

Once again, slowly squeeze the bottle hard and release. What happens? A cloud appears when you release and disappears when you squeeze. The third ingredient in clouds is a drop in air pressure.

 

EXPLANATION:

Water vapour, water in its invisible gaseous state, can be made to condense into the form of small cloud droplets. By adding particles such as the smoke enhances the process of water condensation and by squeezing the bottle causes the air pressure to drop. This creates a cloud!

Try this at home!

http://www.weatherwizkids.com/experiments-cloud.htm

Weather Stations

We are keeping an accurate eye on the weather. Yesterday, we made rain gauges and got them outside... just in time for it to stop raining! Beautiful blue sky since, but we know that we'll get some data out of them in the next week or two.

 Today we constructed Anemometers. These instruments measure wind speed. What fun it was working out how many times they went around in 60 seconds. Once we get some more data, we'll update this post.

 

The Water Cycle

Our Term 4 Inquiry is all about the sky and weather. To start with, we are looking at the Water Cycle. Here is a neat video about the Water Cycle. See if you can name the different stages.

Trip to Otari

We had a fabulous trip to Otari Native Bush. The Year 3's went on Tuesday and our Year 4's went on Wednesday. What an interesting time looking at all sorts of native trees and plants. This is a great place to visit. Thanks so much to the parents who came with us- you are awesome!


If you want to leave a comment- please do so below here instead of on the Photo Peach slide show- thanks

Seed Dispersal - using wind

Lots of plants use the wind to help them with seed dispersal. Today we talked about sycamore seeds and made 'helicopters' to investigate this method of seed dispersal. 

We did some flight testing and measured the distance the helicopters flew then made some modifications to see if they could fly any further. We also talked about the height from which these seeds often fall and how this too helps with the distance they travel.

Look at the dandelion seeds on this flower head. There are so many of them!

Seed dispersal - Kowhai seeds

As part of our Plants and Animals Inquiry we are looking at how plants spread their seed- seed dispersal.

The Kowhai seed is in a pod. We found that it floats on water so could use a stream or river to help with seed dispersal. The yellow seed coat is very thick and would take a long time for the seed to germinate.

Grass Monsters!

2 weeks ago we made some funny monster faces and stuck them on to small pots. They each had a little sack of soil and grass seed in them. For the next week it didn’t seem like anything was going to happen and then last Monday we got a massive surprise to see how much the grass had grown

 and by the end of the week.......

Time for a haircut!

Bumblebees

Bumblebees are amazing!

These incredible creatures are the only insect that makes food for people to eat. Bumble Bees make yummy honey. Honey is used by people on biscuits, in scrumptious cakes and on sandwiches. You can also use honey in lemon drinks and these are good for you when you have a cold.

Bumble bees are very clever because they can smell so that is why they sting. They live in beautiful gardens where their hive is. Bumblebees look like a bug with black and yellow stripes. You normally find them in gardens with flowers. They eat pollen from flowers. They also eat nectar. Their enemies are cats, dogs, and kiwi.

Did you know that Bumblebees arent supposed to fly because their body is bigger than their wings. They do though- really well.

by Vanessa

The Praying Mantis

Did you know there is an awesome insect that prays ?

The Praying Mantis sits on a comfy leaf in the shade and brings their front arms up under the chins.They look like they are praying and that is why they are called a Praying Mantis.

Praying Mantis are a really cool insect.They look lots like a grasshopper and are about the same size.They have heads the shape of a triangle.

The Praying Mantis is an insect that is 25mm to150mm long and has eight long legs.

These insects can live up to about a year and fourteen months.

A Praying Mantis eats yucky and gross spiders and really tiny wasps to gobble it down their throat.

Amazingly, the Praying Mantis can eat something bigger than itself- like small reptiles, birds,small frogs, and lizards!

I found one once in a silver fern bush. The Praying Mantis is a cool insect.

   by  Jason 

The Pukeko

Did you know that the Pukeko can fly? But unlike other  Birds it spends most of its time on the ground.

The Pukeko has red eyes and blue and black feathers. It is about the same size as a small hen but has long red legs. It has a red beak too.

The Pukeko is  found in NZ and lives near cold ponds  and muddy  swamps.

The Pukeko has a lot of enemies like rats, cats, hawks, weasels, and  stoats. 

The Pukeko will fly to get away from enemies.

The Pukeko eats duck eggs, worms and shoots.They can also eat crops from a farmers 

garden and small eels

The Pukeko is cool.It was fun to learn about them and I hope you learned about them too.

by Aydn.

How do Plants Drink?

How do plants drink?
We found a neat website that had an experiment that would help us answer this question.

http://www.sciencebuddies.org/science-fair-projects/project_ideas/PlantBio_p033.shtml#background

                                      Celery also worked well.

 Most of the time, plants get their water from the ground. This means that the plant has to transport the water from its roots up throughout the rest of the plant. How does it do this? Water moves through the plant by means of capillary action. Capillary action occurs when the forces binding a liquid together (cohesion and surface tension) and the forces attracting that bound liquid to another surface (adhesion) are greater than the force of gravity. The plant's stem sucks up water much like a straw does. A process called transpiration helps the capillary action to take place. Transpiration is when the water from the leaves and flower petals evaporates, or, in other words, the water leaves the plant and goes into the surrounding air. As the water evaporates, the plant pulls up more water. (from www.sciencebuddies.org )

Soil Erosion

First we cut out the sides of three plastic bottles. Then we glued them on to a piece of wood using a glue gun- leaving the neck of the bottle sticking out over the edge.

 We then 2/3 filled the bottles with dirt. We carefully got some grass (still with its roots) from outside and put it in one bottle. We filled the next one up with twigs and leaves. The third one we left as is.

We strung a cup under each bottle.  Then we carefully poured the same amount of water into each bottle. The one with grass in it drained clear. The one with the leaves and twigs drained more quickly than the first one and was dirty. The water came out of the third one really quickly and left a trail where it had been. The water was really muddy.

This showed us what happens with soil erosion and how plants and trees really help holding the soil together.

The way water flows- land slides

Today we constructed small villages on a uneven terrain and then watched as we poured water down from the top and saw where the water flowed. If buildings were built on unstable land, or land close to a hill, there was a big chance of it slipping away in a land slide.

Having a closer look

 Carrying on with our 'Land' Inquiry, today we sifted some dirt from the school garden ...





...and had a closer look.