Question

1.      STUDY OF FIGURES AND SURFACES:

Mayank a student of class 7th loves watching and playing with birds of different kinds. One day he had an idea in his mind to make a bird-bath on his garden. His brother who is studying in class 10th helped him to choose the material and shape of the birdbath. They made it in the shape of a cylinder with a hemispherical depression at one end as shown in the Figure below. They opted for the height of the hollow cylinder as 1.45 m and its radius is 30 cm.

By using the above-given information, find the following:

      i.          The curved surface area of the hemisphere is:

                       a.          0.36 m2

                       b.          0.46 m2

                        c.          0.26 m2

                       d.          0.56 m2

     ii.          The curved surface area of the cylinder is:

                       a.          0.78 π m2

                     b.          m2

                        c.           0.87πm2

                       d.           0.87πm2

   iii.          The total surface area of the bird-bath is: (Take   π= )

                       a.          2.3 m2

                       b.          3.3 m2

                        c.          3.5 m2

                       d.          5.3 m2

   iv.          The Total surface area of the cylinder is given by:

                        a.          2 πrh+2 π

                       b.          2πrh+ π

                        c.          2πrh+ 2π

                       d.          Πrh+2π

    v.          During the conversion of a solid from one shape to another the volume of the new shape will:

                       a.          remain unaltered

                       b.          decrease

                        c.          double

                       d.          increase  ​

Answer 1

1 question answer is .0.36 m2