Body volume + annulus - math problems

Number of problems found: 5

  • Round flowerbed
    medzikruzie Around a round flowerbed with a diameter of 6 meters and I will make a sidewalk up to 0.5 meters wide. How much gravel is needed if the layer is to be 5 cm high?
  • Steel tube
    pipe1 The steel tube has an inner diameter of 4 cm and an outer diameter of 4.8 cm. The density of the steel is 7800 kg/m3. Calculate its length if it weighs 15 kg.
  • Metal tube
    pipe2 Calculate the metal tube mass 8dm long with the outer radius 5cm and the inner radius 4.5cm and 1cm3 of this metal is 9.5g.
  • The coil
    lano_1 How many ropes (the diameter 8 mm) fit on the coil (threads are wrapped close together) The coil has dimension: the inner diameter 400mm, the outside diameter 800mm and the length of the coil is 470mm
  • Brass sphere
    ball1 Find the weight of a brass ball with an outer radius of 12 cm, a wall thickness of 20 mm if the density of the brass is 8.5 g/cm3.

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