Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 9 Answered

If a sphere and a hemisphere have the same surface area, find the ratio of their radii if r1 is the radius of the sphere and r2 is the radius of the hemisphere. 
Asked by dhanya_mk2000 | 21 Jan, 2020, 20:32: PM
answered-by-expert Expert Answer
r1 is the radius of sphere
r2 is the radius of hemisphere
Surface space area space of space sphere space equals space 4 πr subscript 1 squared Surface space area space of space hemisphere space equals space 3 πr subscript 2 squared It space is space given space that space their space surface space areas space are space equal rightwards double arrow space 4 πr subscript 1 squared equals 3 πr subscript 2 squared rightwards double arrow space straight r subscript 1 squared over straight r subscript 2 squared equals 3 over 4 rightwards double arrow straight r subscript 1 over straight r subscript 2 equals fraction numerator square root of 3 over denominator 2 end fraction
Answered by Renu Varma | 22 Jan, 2020, 10:19: AM

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 9 - Maths
find the radius of a sphere whose area is 154 cm
Asked by manishgupta8980 | 15 Jul, 2022, 21:17: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
Can you please answer these all questions
question image
Asked by nishimuthu21 | 05 Jul, 2020, 11:06: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
If a sphere and a hemisphere have the same surface area, find the ratio of their radii if r1 is the radius of the sphere and r2 is the radius of the hemisphere. 
Asked by dhanya_mk2000 | 21 Jan, 2020, 20:32: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas
Asked by ppiigoswami | 06 Dec, 2019, 20:53: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
If the area of the top of a hemispherical bowl is 154 cm2. Its volume is 714.65 cm3(app.)  718.67 cm3 (app.) 716.92 cm3 (app.) 720.46 cm3 (app.)
Asked by arajeevshashank | 29 Nov, 2019, 19:21: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
A hemispherical bowl is made of steel, 0.7 cm thick has inner radius 14 cm. It is to be polished from inside and outside. Calculate the total area to be polished.
Asked by Topperlearning User | 18 Oct, 2017, 14:56: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
Two hemispherical bowls are formed by cutting a spherical ball of diameter 28 cm from the centre. Calculate the total surface area of each of the hemispherical bowls so formed.
Asked by Topperlearning User | 18 Oct, 2017, 15:25: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
A toy is in the form of a hemisphere surmounted by a cone of radius 3 cm and height 4 cm. Calculate the surface area of the toy.
Asked by Topperlearning User | 18 Oct, 2017, 14:58: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
If the circumference of the base, a hemispherical dome of a building is 352 cm, find the lateral surface area of the dome.
Asked by Topperlearning User | 18 Oct, 2017, 15:02: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
The hollow sphere, in which the circus motorcyclist performs his stunts, has a radius of 2.8 m. find the area available to the motorcyclist for riding.
Asked by Topperlearning User | 18 Oct, 2017, 15:03: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt