J P Mohindru and Bharat Mohindru Solutions for Chapter: Surface Areas and Volumes, Exercise 4: FOR ASSESSMENT

The slant height of frustum of a cone is $5 \mathrm{cm}$ .If the difference between the radii of its two circular ends is $4 \mathrm{cm}$ , write the height of the frustum.

The volume of the frustum of a cone is $\frac{1}{3}\mathrm{\pi }\left[{r^2}_1+{r_2}^2+r_1{r}_2\right]h$, where $h$ is vertical height of frustum of the frustum and $r_1, r_2$ are the radii of the ends.

A right circular cylinder of radius $r \mathrm{cm}$ and height $h \mathrm{cm}$$\left(h>2r\right)$ just encloses a sphere of diameter

A solid is hemispherical at the bottom and conical (of same radius) above it. If the surface areas of the two parts are equal, then the ratio of its radius and the height of the conical part is :

Volume of two spheres are in the ratio $64:27$. The ratio of their surface areas is

A metallic solid cone is melted to form a solid cylinder of equal radius. If the height of the cylinder is $6 \mathrm{cm}$, then the height of the cone was

Which of the following remains same when one solid is converted to other?

The number of solid spheres, each of diameter $6 \mathrm{cm}$, that can be made by melting a solid metal cylinder of height $45 \mathrm{cm}$ and diameter $4 \mathrm{cm}$ is,: