Question

The height of a cone is equal to its base radius,then the slant height is: (rt. is root)

a)r b)r rt.5 c) r rt.2 d)h rt.5

Answer 1

Let h = height of the cone
Let r = radius of base of cone
slant height = l
$$\begin{gathered} l=\sqrt{r^2+h^2} \\ \Rightarrow l=\sqrt{r^2+r^2}(asr=hgiven) \\ \Rightarrow l=\sqrt{2r^2}=\sqrt{2\times r\times r}=r\sqrt{2} \end{gathered}$$