![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
After cutting a 4-meter-long cylindrical steel into two equal sections, the surface area increases by 0.28 square decimeter. If each cubic decimeter of steel weighs 7.8 kg, this will be a big problem How many kilos does the root weigh?
After the cylindrical steel is cut into two equal sections, the surface area of the two cylinders increases
Bottom area: 0.28 △ 2 = 0.14 (square decimeter)
4m = 40m
Volume of cylinder: 0.14 × 40 = 5.6 (cubic decimeter)
Weight: 5.6 × 7.8 = 43.68 (kg)
RELATED INFORMATIONS
- 1. Cut a 1 meter long cylindrical steel with a diameter of 2 decimeters into two sections and increase its surface area by () square decimeters A. 3.14B. 6.28C. 12.56
- 2. How many square decimeters has the surface area increased when a 2.5-meter-long cylindrical steel with a bottom diameter of 2 decimeters is divided into three sections?
- 3. Cut a 1-meter-long cylindrical steel with a bottom diameter of 2 decimeters into two sections and increase its surface area () A. 6.28 square decimeters B. 9.42 square decimeters C. 12.56 square decimeters
- 4. How to increase the surface area of a one meter long cylindrical steel with a bottom diameter of 2 decimeters? It's simple To be more specific, why
- 5. How many square decimeters has the surface area increased when a 2.5-meter-long cylindrical steel with a bottom diameter of 2 decimeters is divided into three sections?
- 6. When a 1.5-meter-long cylindrical steel is cut into three sections on average, the total surface area of the three sections increases by 12.56 square decimeters. It is known that the weight of each cubic decimeter of steel is 7.8 kg. What is the weight of one section of steel?
- 7. Cut a 1.2-meter-long cylindrical steel into three sections, and the surface area increases by 12.56 square decimeters?
- 8. Divide an 8-decimeter-long cylindrical steel into two sections, and increase the surface area by 25.12 square decimeters. Calculate the volume of the original steel?
- 9. A 16 decimeter long cylinder steel is cut into three shorter cylinders, and its surface area is increased by 24 square decimeters. What is the original volume of this steel
- 10. After a 1-meter-long cylindrical steel is cut into two sections, the surface area increases by 6.28 square decimeters, and the original volume of the steel is______ Cubic meter
- 11. After a 1.5-meter-long cylindrical steel is cut into three sections, the surface area increases by 9.6 square decimeters. What is the original volume of this steel?
- 12. Solution set of inequality (absolute value of 1 + x) / (absolute value of x-1) ≥ 3 Ask for specific steps The answer is [- 2, - 1) ∪ (1,2]
- 13. If the point P (x, y) is on the circle (X-2) ^ 2 + y ^ 2 = 3, then the sum of the maximum and minimum value of Y / X is? (seeking process.)
- 14. If the square of 2x - ax + B decomposes the factor, we can get (2x-1) (x + 2) to find the value of a and B
- 15. A cylinder with a surface area of 50 square centimeters has a bottom area of 15 square centimeters. Two such cylinders form a large cylinder. What is the surface area of this large cylinder
- 16. 99.9-46.3 = (calculated by simple method)
- 17. Given the function f (x) = x2-2x, the area of the region formed by the point (x, y) satisfying the condition f (x) + F (y) ≤ 0f (x) − f (y) ≥ 0 is () A. 4πB. 2πC. 3π2D. π
- 18. Mathematical simplification in evaluation 1 / 2 - [x-3 (x-1)] - 2 (1 / 2-x), where x = 2 No one >^
- 19. If y = x * sin2x, Dy =?
- 20. 98.1*0.01+5*9.81+0.049*981