Maths-
General
Easy
Question
The area of the slant surface of a cone is 3080 sq. m. If the radius of its base is 28 m, find its height ?
- 22 m
- 21 m
- 31 m
- 41 m
Hint:
Slant surface of a cone is curved surface
Curved Surface area of cone = πrL
Where L is slant height
L = 
The correct answer is: 21 m
We have given the cone dimensions
Radius, r = 28 m
Let height of cone be h
We have to find the height of the cone
CSA of cone = 3080 m2
We know that CSA of cone = πrL
h = 
Put this value in the CSA formula
3080 = πrL
3080 = 
x 28 x L
3080 = 22 x 4 x L
3080 = 88 x L
L = 35
Squaring on both sides
1225 = L2
1225 = 
)2
1225 = h2 + 784
h2= 441
h = 21 m
Therefore, correct option is b) 21 m
Put this value in the CSA formula
x 28 x LSquaring on both sides
)2Therefore, correct option is b) 21 m
Related Questions to study
Maths-
Factor the given expression completely.
Factor the given expression completely.
Maths-General
Maths-
A vessel in the form of a inverted cone is filled with water to the brim. Its height is 20 cm and diameter is 16.8 cm Two equal solid cones are dropped in it , so that they are fully submerged.AS a result , one third of the water in the original cone overflows. What is the volume of each of the solid cones submerged?
A vessel in the form of a inverted cone is filled with water to the brim. Its height is 20 cm and diameter is 16.8 cm Two equal solid cones are dropped in it , so that they are fully submerged.AS a result , one third of the water in the original cone overflows. What is the volume of each of the solid cones submerged?
Maths-General
Maths-
A conical tent can accommodate 11 persons . Every person need 4 sq. m of land 20 cm3 of air. Find the height of the tent just for 11 persons .
A conical tent can accommodate 11 persons . Every person need 4 sq. m of land 20 cm3 of air. Find the height of the tent just for 11 persons .
Maths-General
Maths-
Factor the given expression completely.
Factor the given expression completely.
Maths-General
Maths-
The heights of 2 cones are same and the radii of their bases are in the ratio 2:3 , ratio of their volumes is
The heights of 2 cones are same and the radii of their bases are in the ratio 2:3 , ratio of their volumes is
Maths-General
Maths-
Write the factored form of the given expression.
Write the factored form of the given expression.
Maths-General
Maths-
Factor the given expression completely.
Factor the given expression completely.
Maths-General
Maths-
The radii of two cones are same and the ratio of their heights is 2:3, The ratio of their volumes is
The radii of two cones are same and the ratio of their heights is 2:3, The ratio of their volumes is
Maths-General
Maths-
A solid right circular cone of height 20 cm and base radius 15 cm is melted and casted into smaller cones of equal sizes of height 5 cm and base radius 1.5 cm. Find how many cones are made.
A solid right circular cone of height 20 cm and base radius 15 cm is melted and casted into smaller cones of equal sizes of height 5 cm and base radius 1.5 cm. Find how many cones are made.
Maths-General
Maths-
Write the factored form of the given expression.
Write the factored form of the given expression.
Maths-General
Maths-
Dimensions of a room are 5m
12m7m, calculate the diagonal of the room and cost of flooring at the room Rs 2
Dimensions of a room are 5m12m7m, calculate the diagonal of the room and cost of flooring at the room Rs 2
Maths-General
Maths-
A cone has a base diameter of 6 cm and a vertical height of 8 cm. Calculate the volume of the cone in cubic centimetres.
A cone has a base diameter of 6 cm and a vertical height of 8 cm. Calculate the volume of the cone in cubic centimetres.
Maths-General
Maths-
What is the length of the longest pole that can be fit in the room of dimensions 5m x 10m x 5m
What is the length of the longest pole that can be fit in the room of dimensions 5m x 10m x 5m
Maths-General
Maths-
The square on the diagonal of a cube has an area of 192 cm2. Find the T.S.A of the cube.
The square on the diagonal of a cube has an area of 192 cm2. Find the T.S.A of the cube.
Maths-General
Maths-
Two adjacent sides of the right-angle pf a right-angled triangle are 3 cm and 4 cm. This triangle is revolved around the side of length 3 cm. Find the volume of the cone thus formed. Find also the slant height of the cone (π =3.14).
Two adjacent sides of the right-angle pf a right-angled triangle are 3 cm and 4 cm. This triangle is revolved around the side of length 3 cm. Find the volume of the cone thus formed. Find also the slant height of the cone (π =3.14).
Maths-General
