A cylinder with a bottom diameter of 10 cm and a height of 15 cm is cut into two half cylinders along the diameter. What is the surface area of a half cylinder

A cylinder with a bottom diameter of 10 cm and a height of 15 cm is cut into two half cylinders along the diameter. What is the surface area of a half cylinder

The increase of surface area is the surface area of the section, s = 2x22x10 = 440 square centimeter

After a section of cylinder wood with a diameter of 10 cm is uncovered longitudinally along the diameter of the bottom surface, the surface area increases by 200 square cm. What is the original volume of this section?

The height of the cylinder is: 200 ／ 2 ／ 10, = 100 ／ 10, = 10 (CM); so the volume of the cylinder is: 3.14 × (10 ／ 2) 2 × 10, = 3.14 × 25 × 10, = 785 (cm3); a: the original volume of the cylinder is 785 cm3

When a cylinder with a diameter of 10cm at the bottom and a height of 15cm is cut into a cuboid, the surface area increases by () square centimeter,

After the cuboid is assembled, only two congruent sides are added to the original surface area. These two sides are rectangular, length = bottom radius, and height is the height of the cylinder. Therefore, the surface area is increased, 5 * 15 * 2 = 150 (square centimeter)