Winter Science

How does a sled work?????

I went sledding a lot this week and wondered how on earth does this thing work?! I did some researching in my science books and by watching Science Max and learned that sleds work with FRICTION. Science Max has a whole episode just to teach about friction which was really helpful.

Basically, there is a force called friction between the snow surface and the sled surface. Because both surfaces are smooth there is a lot less resistance than if you try to sled down a hill with grass on it instead of snow.

How are icicles made??????

I went to my great grandma and grandpa's house yesterday and they have TONS of icicles. We had so much fun breaking them and figuring out what was inside them.

I wondered how they are made. Some of them have a spiral pattern that is very interesting.

In my research I discovered that icicles are made in a similar way to how stalactites form inside caves. These form over time. Icicles are made on days when it is very cold, usually it is below freezing outside. This means it is less than 32 degrees in the air. But, the sunshine melts the snow or ice that is on a surface like a roof or fence or car. Because the air is still so cold, it will become frozen again as it drips. According to my scientific research the base grows much faster than the tip and gravity keeps the water traveling towards the grown, which is why it takes its pointed shape. The bottom is always the biggest part and it gets smaller and smaller until the tip. That is why the base is the hardest part to break.