2015 · Q64
30 metallic cylinders of same size are melted and cast in the form of cones having the same radius and height as those of the cylinders Consider the following statements :
Statement IA maximum of 90 cones will be obtained.
Statement IIThe Curved surface of the cylinder can be flattened in the shape of a rectangle but the curved surface of the cone when flattened has the shape of triangle.
Which one of the following is correct in respect of the above ?
Elementary MathematicsQuadrilaterals and Polygons
- ABoth Statement I and Statement II are correct and Statement II is the correct explanation of Statement I
- BBoth Statement I and Statement II are correct and Statement II is not the correct explanation of Statement I
- CStatement I is correct but Statement II is not correct
- DStatement I is not correct but Statement II is correct
Explanation
Each cylinder (volume pi*r^2*h) makes 3 cones (volume pi*r^2*h/3), so 30 cylinders give 90 cones (I true); a cone's curved surface unrolls to a sector, not a triangle (II false). Hence option (c).