Solution:
On rotating a right-angled triangular lamina AOB about OA, it generates a cone. The point A is the vertex of a cone. Its base is a circle with centre O and radius OB. The length OA is the height of the cone and the length AB is called its slant height.
Clearly, $\angle\text{AOB}=90^\circ$ Let the radius of the base = r unit, height = h units and slant height = l unit, then $\text{l}^2=\text{h}^2+\text{r}^2\Rightarrow\text{l}=\sqrt{\text{h}^2+\text{r}^2}$Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
If any two sides of a right triangle are respectively equal to two sides of other right triangle then the two triangle are congruent.