Question

The height of a cone is 20m and its base
radius is 50cm - Find the curned surface
area and the total surface area
of the cone.​

Answer 1

Answer:

given height= 20cm ,

base radius = 50cm ,

To find: CSA of cone and TSA of cone

Solve : CSA of cone = πrl

= 22\7 x 50 x 20

3142.8..cm2

and TSA of cone = πr(l+r)

= 22\7 x 50 ( 20+50 )

= 22\7 x 50 ( 70)

= 1100cm2

this is the final answer.!

Answer 2

Answer:

• CSA of cone = 31.5 m²
• TSA of cone = 32 3 m²

Step-by-step explanation:

Given that :

• Height of cone = 20 m
• Radius = 50 cm = 0.5 m

To find :

• The curved surface area of cone.
• The total surface area of cone.

Solution :

First, we have to find the slant height (l).

Slant height = $\sqrt{r^2 + h^2}$

⇒ l = $\sqrt{(0.5)^2 + (20)^2}$

⇒ l = $\sqrt{0.25 + 400}$

⇒ l = $\sqrt{400.25}$

⇒ l = 20 m (approx)

We know that,

CSA of cone = πrl

                          = $\dfrac{22}{7}$ * 0.5 * 20

                          = $\dfrac{220}{7}$

                          = 31.5 m² (approx)

Also,

TSA of cone = πr (l + r)

                          =  $\dfrac{22}{7}$ * 0.5 ( 20 + 0.5 )

                          =  $\dfrac{22}{7}$ * 10.25

                          = $\dfrac{225.5}{7}$

                          = 32.3 m² (approx)

Hence,

• CSA of cone = 31.5 m².
• TSA of cone = 32.3 m².