Question

Area of the base of right circular cone is 2826 square cm.if the hight is 4cm and slant hight is 5 cm find it's volume and area of curved surface

Answer 1

Given:

☛ area of base of right circular cone = 2826 cm²

☛ height, h = 4 cm

☛ slant height, l = 5 cm

To Find:

☛ Volume of right circular cone

☛ area of curved surface

Solution:

We know,

==> Volume of Cone = 1/3 πr²h

==> V = 1/3 × 2826 × 4 { given, πr² = 2826 }

==> V = 942 × 4

==> [ V = 3768 cm³ ]

Now,

==> area of base = πr²

==> 2826 = πr²

==> r² = 2826 / π

==> r = √19782 / √π

Also,

==> Curved Surface Area of Cone = πrl

==> C.S.A = π × √19728/√x × 5

==> C.S.A = 5π × √19728 / √π × √π / √π

==> C.S.A = 5π√π × √19728 / π

==> C.S.A = 5√π × √19728

==> C.S.A = 5 × √3.14 × 140.45

==> C.S.A = 8.85 × 140.45

==> [ C.S.A = 1242.9825 cm² ]