Question

The height of a cone is 15 cm. If its volume is 1570 cm³, find the radius of its base. [Use π = 3.14]

Answer 1

Height (h) of cone = 15 cm

Let the radius of the cone be r.

Volume of cone = 1570 cm³

`1/3pir^2h` = 1570 cm³

`rArr(1/3xx3.14xx r^2 xx15) cm` = 1570 cm³

 ⇒ `1/3 xx 314/100 xxr^2 xx 15 = 1570`

 ⇒ `r^2 = (1570 xx3 xx100)/(314 xx 15)`

 ⇒ r² = 100 cm²

 ⇒ r = 10 cm

Thus, the required radius of the base is 10 cm.