What are the precautions when using compasses?

Compass is a tool used to draw circles or arcs in mathematics and drawing. Compasses are usually made of metal and consist of two hinged parts, which can be adjusted. Compasses are divided into ordinary compasses, spring compasses, point compasses, beam compasses, old compasses, mechanical pencil compasses and movable small compasses. The precautions for pupils to use compasses are as follows.

1, the height between the two legs of the compass should be the same.

2. In the process of drawing a circle, the compasses should be slightly inclined by about 30 degrees to make the drawn round lines smooth.

In the process of drawing a circle, the end with the needle (that is, the center of the circle) can't move.

4. In the process of drawing a circle, the distance between two feet (i.e. radius) cannot be changed.

Pay attention to the above problems when using the compass. The compass has a needle tip. Children should not hurt themselves when using it. There are many dangers for students to use Chinese. Besides compasses, other stationery should also be paid attention to when using. Here is a brief introduction to campus safety knowledge, so that everyone knows how to protect themselves.

1, don't play with pencils and pens, it's easy to break the nib and hurt yourself. Don't bite the pencil with your mouth, because the colored paint on the surface of the pencil contains lead, which is easy to cause "lead poisoning" after eating it by mistake. Besides, if your buddy accidentally bumps into you, the pencil will also scratch your mouth.

2, don't play with the ruler, because the plastic ruler is easy to break, it will collapse to others or scratch your hands.

3, compasses, knives and other stationery is very sharp, should be properly placed. You shouldn't run with these sharp things. If you fall down carelessly, they may hurt you.

Some erasers are fragrant, but the chemicals in them are harmful to human body, so you can't chew them with your mouth.