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There is a mess of wire which can't be straightened out. Please use your measuring tools to measure its length quickly It is required to write out the main steps and calculation formula of the measurement method 1. Give you a scale with the minimum scale value of mm and a pallet balance Here is a round pencil, a ruler and a large cup
1 balance
First weigh the total mass M1, then cut the next section straight to weigh the mass m2, and measure the length L1 of the cut section, then the total length L = M1 * L1 / m2
two
1. Fill a large number of cups with water and record the water scale with a pencil
2. Immerse the whole thin wire in water and record the scale V2 of water at this time
3. The volume of wire V3 = v2-v1
4. Measure the wire diameter d with a scale
5. Calculate the cross-sectional area of wire s = 1 / 4 (Π d * d)
6. Length of wire L = V3 / s
It's the first day of junior high school. So am I!
There are three cube metal blocks of different volumes, one of which is hollow. Please use the scale and balance to find out the hollow and write your method
Answer: ① measure the mass m of the cube metal block with the adjusted balance; ② measure the side length L of the cube metal block with the scale; ③ the density of the metal block: ρ = MV = ML3. Compare the density of the three cubes, the one with smaller density is hollow
It can be used to measure the volume of irregular solid or liquid
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RELATED INFORMATIONS
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- 13. To measure the diameter of a thin wire, there is an 80cm wire, a pencil and a millimeter scale. Design the measurement scheme and write the results
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- 15. A student measured the length of an object with a ruler with the minimum scale value of 1 mm, and made the following records: ① 18.74 cm, ② 1.87 × 10 quartic mm A student measured the length of an object with a ruler with the minimum scale value of 1 mm, and made the following records: ① 18.74 cm, ② 1.87 × 10 quartic mm, ③ 0.187 m, ④ 1.874 × 10 quadratic mm A. ① and ③ B. (1) and (4) C. (2) and (4) D. All meet the requirements
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