What ruler should I use to know how long the school playground is?
To know how long the school playground is, you should use a steel tape or tape measure of more than 50 meters.
The school playground is a place for physical exercise, which refers to the special place for school physical education and teaching activities. Because the school playground is generally large, it needs to be measured with a steel tape or tape measure of more than 50 meters.
Rulers are divided into straightedge, tape measure, steel rule, vernier caliper, micrometer, etc.
A ruler, also called a middle ruler, has a precise straight edge and is used for measuring length and drawing. Rulers are widely used in mathematics, measurement, engineering and other disciplines. A ruler with a precise ruler. Rulers are used to measure straightness and flatness by light gap method, and can also be used to check length and size together with measuring blocks.
Tape measure is a common measuring tool in daily life. Divided into fiber tape measure, tape measure, waist measure and so on. What we often see is a steel tape measure, which is often used in construction and decoration, and is also one of the necessary tools for families. Lu Banchi, Feng Shui ruler and secretary also belong to steel tape measure. The main type of tape measure is steel tape measure, followed by fiber tape measure, which is the tape measure that everyone often sees. Many people say it's a cloth tape measure and a waist tape measure.
Steel ruler is a long ruler made of thin steel plate, which can be rolled into a metal round box, so it is also called steel tape measure. The width of the ruler is about 10- 15mm, and the length is 20m, 30m and 50m. Steel straightedge has high tensile strength and is not easy to stretch, so it has high distance accuracy and is often used in engineering survey. A steel ruler is a steel tape measure. The steel rule is basically divided into centimeters, and every meter has digital remarks, which is suitable for general distance measurement.
Vernier caliper is a measuring tool for measuring length, inside and outside diameter and depth. The vernier caliper consists of a main ruler and a sliding vernier attached to the main ruler. The main ruler is usually in millimeters, while the cursor has 10, 20 or 50 scales. Vernier calipers can be divided into 10-degree vernier calipers, 20-degree vernier calipers and 50-degree vernier calipers.
Outside micrometer, also known as spiral micrometer, is usually referred to as "micrometer" for short. It is a more precise length measuring instrument than vernier caliper, with the accuracy of 0.0 1mm, 0.02mm and 0.05mm, and with the estimated 1, it can be read to the third place (one thousandth) after the decimal point, so it is called micrometer.
Materials on the ground of the school playground
1, plastic runway. The plastic track is mainly paved with environmentally friendly rubber particles and polyurethane emulsion, which has good elasticity, protects sports injuries and is dustproof, and can be used immediately after rain. Of course, there are many kinds of materials for the plastic track, and the appropriate type should be selected according to different functional requirements.
2. Football field. There are two ways to lay a football field: natural grass (real grass) and artificial grass (fake grass). Natural grass can be transplanted or planted in situ. There are many kinds of artificial grass, mainly the shape, size and density of grass filaments.
3. Basketball court. The ground materials of basketball court include silicon PU, hard acrylic acid, elastic acrylic acid, EPDM, suspended floor, etc. The materials used in different venues are also different, and the construction technology and cost are also different.