Advice 1: How to make a scan of the cylinder

The cylinder is one of the basic three-dimensional figures. The cylinders are elliptic, circular and parabolic. The form of the cylinder is determined by which flat figure lies at its base. The most common (and simple to construct) case is a straight circular cylinder.
How to make a scan of the cylinder
You will need
  • paper;
  • pencil;
  • - the range;
  • a pair of compasses.
Instruction
1
Direct circular cylinder is defined by two quantities: the base radius R and height of the cylinder H. Knowing the radius of the circle lying at the base of the cylinder, it is easy to compute the circumference of the base. This value is necessary to build a scanner. It is equal to L = 2NR, where Π=3,14159.
2
Any cylinder has two bases and the lateral surface. In a right circular cylinder both bases are circles. Side surface while unrolling it onto the plane looks like a rectangle with sides L (length of the circumference of the base) and H (height of cylinder). Thus, the scan of a right circular cylinder contains a rectangle and two circles.
3
Construct with compass two of the same circle of radius R. Then use the ruler and pencil, draw a rectangle with length H and height L = 2NR. Provide fields for the bonding of the figure. It is convenient to make a long strip for gluing on one side H of the rectangle and a small triangular field on both sides of the L. the Total sweep look at the picture.
Note
If the cylinder is elliptic, the base it is an ellipse. Then in the above algorithm instead of circles draw ellipses, and the length L1 of the ellipse calculated according to the following table. The rectangle (the lateral surface) in this case dimensions H x L1.

In the case of the truncated at an angle to the base of the cylinder will have to build the surface of the cross section in true size.

Advice 2 : How to make volumetric square of paper

Volumetric square of paper – it is a cube that is easy to make yourself, following simple instructions. You can do this with your children – it will be interesting to construct this geometrical figure.
How to make volumetric square of paper
You will need
  • paper;
  • - cardboard;
  • - the range;
  • pencil;
  • - scissors;
  • glue;
  • - the markers;
  • - colored paper;
  • - paint.
Instruction
1
On the album sheet of paper with a ruler and pencil, draw a net of a cube. It must have six faces, each a square. In the scan position them so that I had to glue as little as possible edges. Four lateral sides place back to back, and top face and the base - side sweep.
2
Strengthen the cube inside a cardboard frame, making exactly the same scan, but without top and without Foundation. Draw the frame by a few millimeters less than the base cube.
3
Pririsuyte special valves for sweeps, then they will be smeared with glue. Often when gluing the valve is glued directly to the face of the cube, but if the paper is very thin, then bond the flaps together, and the edges will remain intact.
4
Carefully glue the frame, then around it - a cube. Glue it on top of colored paper, you can make application, to paint it with paints, markers or crayons – that you and your helpers have enough imagination. If you produce a dice for Board games, write on its sides the number of points. But do not forget that opposing parties in the amount they should give the number 7.
5
If you want to make not the dice, but to surround the square (though this figure and not in the geometry, since the square is planar, planimetric figure), use the origami.
6
Take a square sheet with a side of 15 cm.
7
Fold in half to form a crease, unfold it back.
8
Now the same sheet, fold the edges to the center of the bend. Turn the leaf over, then fold each of the opposite corners towards the center to form a trapezoid.
9
Fold the corners of the trapezoid on the opposite side to the center to make a square. Thus you get "the square".
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