1, meters and centimeters are units for measuring the length of an object. 1 m = 100 cm

The centimeter can be represented by the letter cm, and the meter can be represented by the letter m? 1m= 100cm, and the forward speed between meters and centimeters is 100.

2, the method of measuring the length of the object with a ruler

When measuring the length of an object with a ruler, aim the 0 scale of the ruler at one end of the object, and then look at the scale corresponding to the other end of the object, which is several centimeters relative to the scale; If one end of an object faces other scales instead of the 0 scale, the difference between the two scales facing the two ends of the object is the length of the object.

general idea

Comparing the length of an object depends on whether the length unit is unified; If it is not unified, it is necessary to unify the units first and then compare them. When measuring the length of a shorter object, the unit is usually "cm"; When measuring the length of a long object, the unit is usually "meter". The length of an object can be judged by combining the unit with the data or referring to the object, and the approximate length of the object can be estimated by combining with real life.

2. Common tools for measuring length are: ruler, tape measure, vernier caliper and screw micrometer (also called micrometer). Other scales, such as trigonometry and tape measure, are also commonly used to measure length.

1, ruler

A ruler, also called a middle ruler, has a precise straight edge and is used for measuring length and drawing. Widely used in mathematics, measurement, engineering and other disciplines.

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.

Different materials, such as iron, wood, plastic, etc. A ruler has a certain hardness, otherwise it is a soft ruler. ? The minimum scale is generally1mm. The scale unit is usually centimeters.

2. Tape measure

Tape measure is a common measuring tool in daily life. 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. Divided into fiber tape measure, tape measure, waist measure and so on.

The tape measure can be rolled up because it has a spring. When measuring the length, the length of the ruler and the spring is actually lengthened. Once the measurement is completed, the spring in the tape measure will automatically shrink, and the ruler will also shrink under the action of the spring force, so the tape measure will be rolled up.

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.

3. Vernier caliper

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.

As a common measuring tool, vernier caliper can be used in the following four aspects: 1) measuring the width of workpiece 2) measuring the outer diameter of workpiece 3) measuring the inner diameter of workpiece 4) measuring the depth of workpiece.

Ordinary vernier calipers can be divided into three types according to their accuracy: 0. 1mm, 0.05mm and 0.02 mm. ..

4. Screw micrometer

Screw micrometer, also known as micrometer, screw micrometer and dividing card, is a tool for measuring length more accurately than vernier caliper. It can accurately measure the length to 0.0 1 mm, and the measuring range is several centimeters.

Screw micrometer can be divided into mechanical micrometer and electronic micrometer.