Method for make children's manual telephone

1, with both sides folded in the middle.

2. Fold the four corners back.

Turn it over and fold it back along the dotted line.

4, respectively to both sides.

5. done.

The second type

2. Draw a pattern on the paper cup with a brush.

3. Cut the toothpick into 5cm long with wallpaper knife, which is smaller than the width of the cup bottom 1cm, and put it into the cup.

4. Poke a small hole in the bottom of the paper cup with a toothpick, insert the cotton thread, take it out of the cup mouth, and then tie the cotton thread to the cut toothpick.

5. Insert the other end of the cotton thread into the cup and take it out from the mouth of the cup.

6. The production is finished.

Preparation materials: two paper cups, cotton thread, toothpick, wallpaper knife, scissors and brush.

principle

Sound can spread through the medium, and the paper cup phone is the principle of sound vibration. Sound is transmitted by vibration, and it must pass through the line as the medium. If it is not tight, it will be affected by gravity, the conductivity will be reduced, and there is not enough energy to vibrate.

Similarly, the tight line means that there is a medium, but it should be used at close range, otherwise it will not vibrate and the sound will not be transmitted normally. Moreover, the hole of the paper cup should not be too large, and the sound transmission effect of gas is worse than that of solid.