Sphere - problems - page 3

  1. Sphere vs cube
    koule_krychle How many % of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?
  2. Cube from sphere
    sphere_cube What largest surface area (in cm2) can have a cube that was cut out of a sphere with radius 43 cm?
  3. Average speed
    earth_2 What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
  4. Earth's surface
    earth_globe The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
  5. Float boya
    boya A 0.5 meter spherical float is used as a location mark for a fishing boat anchor. It floats in salt water. Find the depth to which the float sinks if the material of which the float is made weighs 8 kilograms per cubic meter and salt water weighs 1027 kg/m
  6. Spheres in sphere
    Spheres_in_sphere How many spheres with a radius of 15 cm can fits into the larger sphere with a radius of 150 cm?
  7. Cube and sphere
    gule_1 Cube with the surface area 150 cm2 is described sphere. What is sphere surface?
  8. Billiard balls
    balls_billiard A layer of ivory billiard balls of radius 6.35 cm is in the form of a square. The balls are arranged so that each ball is tangent to every one adjacent to it. In the spaces between sets of 4 adjacent balls other balls rest, equal in size to the original. T
  9. Hollow sphere
    sphere2 The volume of the hollow ball is 3432 cm3. What is its internal radius when the wall thickness is 3 cm?
  10. Cube in sphere
    sphere4 The sphere is inscribed cube with edge 8 cm. Find the radius of the sphere.
  11. Stadium
    sphere_segment A domed stadium is in the shape of spherical segment with a base radius of 150 m. The dome must contain a volume of 3500000 m³. Determine the height of the dome at its centre to the nearest tenth of a meter.
  12. Fit ball
    fitball What is the size of the surface of Gymball (FIT - ball) with a diameter of 65 cm?
  13. Inscribed sphere
    ball-in-cube How many % of the volume of the cube whose edge is 6 meters long is a volume of a sphere inscribed in that cube?
  14. Sphere radius
    koule_krychle_2 The surface of the sphere is 60 cm square. Calculate its radius; result round to tenth of cm.
  15. Inscribed sphere
    cubes2_7 How many percents of the cube volume takes the sphere inscribed into it?
  16. Sphere equation
    sphere2 Obtain the equation of sphere its centre on the line 3x+2z=0=4x-5y and passes through the points (0,-2,-4) and (2,-1,1).
  17. Equilateral cylinder
    sphere_in_cylinder A sphere is inserted into the rotating equilateral cylinder (touching the bases and the shell). Prove that the cylinder has both a volume and a surface half larger than an inscribed sphere.
  18. Cube, cuboid, and sphere
    cubes3_8 Volumes of a cube and a cuboid are in ratio 3: 2. Volumes of sphere and cuboid are in ratio 1: 3. In what ratio are the volumes of cube, cuboid, and sphere?
  19. Sphere from tree points
    sphere2_1 Equation of sphere with three point (a,0,0), (0, a,0), (0,0, a) and center lies on plane x+y+z=a
  20. Cube into sphere
    cube_sphere_in The cube has brushed a sphere as large as possible. Determine how much percent was the waste.

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