NCERT Exemplar Class 10 | Chapter 12 Surface Area & Volume |Sample Questions + Exercise12.3(1–6)

Описание: sample question 1:A cone of maximum size is carved out from a cube of edge 14 cm find the surface area of the cone and the remaining solid left out after the cone carved out.

Sample Question 2:
A solid metallic sphere of radius 10.5 cm is melted and recast into a number of smaller cones, each of radius 3.5 cm and height 3 cm. Find the number of cones so formed.

Sample Question 3:
A canal is 300 cm wide and 120 cm deep. The water in the canal is flowing with a speed of 20 km/h. How much area will it irrigate in 20 minutes if 8 cm of standing water is desired?

Sample Question 4:
A cone of radius 4 cm is divided into two parts by drawing a plane through the mid point of its axis and parallel to its base. Compare the volumes of the two parts.

sample question -5 Three cubes of a metal whose edges are in the ratio 3 :4:5 are melted and converted into a single cube whose diagonal is 12 √3 cm find the edges of the three cubes.
Exercise -12.3
1.Three metallic solid cubes whose edges are 3 cm, 4 cm and 5 cm are melted and formed into a single cube. Find the edge of the cube so formed.
2.How many shots each having diameter 3 cm can be made from a cuboidal lead solid of dimensions 9 cm × 11 cm × 12 cm?

4.A cone of radius 8 cm and height 12 cm is divided into two parts by a plane through the mid-point of its axis parallel to its base. Find the ratio of the volumes of two parts.
5.Two identical cubes each of volume 64 cm³ are joined together end to end. What is the surface area of the resulting cuboid?
6.From a solid cube of side 7 cm, a conical cavity of height 7 cm and radius 3 cm is hollowed out. Find the volume of the remaining solid.