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Space
NASA’s Space Place Primary level space games
Sci jinks Secondary level (mostly weather) simulations (NASA)
Mechanics and technology
Puzzles
The magic triangle
A triangle can be made by arranging 4 shapes on a 5 x 13 grid.
By re-arranging the shapes a new triangle can be made.
The pieces in the lower triangle are exactly the same as those in the upper triangle, but now seem to take up less space so there is one blank square
Where does the white square come from?
[simple_tooltip content=’This trick makes use of an optical illusion. Even though the triangles appear identical the longer edge of the triangle is not a straight line. It bends down lightly in triangle A and bulges upwards slightly in trangle B. Try printing the triangles out and place a ruler against the longer side.’]Hover your mouse here for the solution[/simple_tooltip]
Here is another similar puzzle:
4 similar qudrilateral shapes are arranged into a square.
If each is rotated by 180º they make a similar square but there is a piece missing in the middle.
Where does the extra space come from?
[simple_tooltip content=’The new square is very slightly larger (0.8%) than the original square. For more of the maths on this and the puzzle above goggle Wikipaedia https://en.wikipedia.org/wiki/Missing_square_puzzle ‘]Hover your mouse here for the solution[/simple_tooltip]
Bear Puzzle
A bear walks 1 kilometre south, 1 kilometre west and then 1 kilometre north
He ends up in exactly the same place he started.
What colour is the bear?
[simple_tooltip content=’The bear must be white. The ony place where you could walk 1km South, 1km West (or east) and then 1km north … and end up where you started could be the North Pole so he must be a Polar bear’]Hover your mouse here for the solution[/simple_tooltip]
4 litres of water problem
You are camping by the edge of a stream and a recipe calls for EXACTLY 4 litres of water.
Unfortunately, you only have two empty containers, one that holds 3 litres of water and one that holds 5 litres.
How can you get exactly 4 litres (you can fill and empty the containers as many times as you like using water from the stream).
[simple_tooltip content=’Fill the 3 litre container with water. Pour this water into the 5 litre container.
Fill the 3 litre container again. Again pour as much of this water as you can into the 5 litre container. This will leave 1 litre of water in the 3 litre container
Empty the 5 litre container and pour the one litre from the 3 litre into the 5 litre container.
Fill up the 3 litre container again and pour this into the 5 litre container – making 4 litres all together.’]Hover your mouse here for the solution[/simple_tooltip]
Physics
Game about moments (the lever law) Simple moment simulation
Forces and motion Simulation about the Lever Law
Springs and Hookes Law Learn about Hookes Law
How friction heats up a surface (Kinetic theory simulation)
Density Learn about density by seeing what floats
Energy Change Kinetic, potential and internal energy change
Colour mixing What happens colours are mixed together
The Light Game Learn about red blue and green light
Chemistry
pH scale Test the pH of different substances