10.one cut follow surface connected special before ring along instead show |
Take any long piece of paper. Now glue the ends of the paper together. You have made a (1)
. Take a second long piece of paper. Twist (旋转) the paper once and glue the ends together. Now you have made a Mobius band (莫比乌斯带). For people who study maths, this band is (2)
.
This strange hand was (3)
made in the 1800s by a German man named August Mobius. Mr. Mobius studied maths. He wanted to find a way (4)
how this band works with maths. Believe it or not, this band has only one (5)
. You can find this out for yourself.
If you draw a line on the surface of the paper (6)
you twist and glue it, the line is only on one side of the paper. The paper has two surfaces. However, if you draw a line after you make the Mobius band, you can (7)
the line around all sides of the paper. In other words, the Mobius band must have only one surface.
It is also kind of fun to see what happens when you (8)
the band. If you cut the Mobius band in half (9)
the line you draw , you do not get two Mobius bands. (10)
, after you cut the band, it turns into one large twisted ring. Then, if you cut this ring in half along the middle of the band again, you get two (11)
Mobius bands.
Try it!