Page 1 - WS3

SAI International School

CLASS - X

Mathematics
CHAPTER-12: Surface Areas and Volumes

Lab Activity-3

SUBTOPIC: Surface Area of Sphere

Surface Area of a Sphere

Objective
To find the surface area of sphere with the help of an activity.

Prerequisite Knowledge
Curved surface area (C.S. A.) of a right circular cylinder = (where r = radius of the
base and h = height of the cylinder)

Materials Required
A solid spherical plastic ball, a cylinder with height equal to the diameter of the sphere,
thread, cutter, pins, sketch pen etc. (Let radius of sphere be rand height of the cylinder
be h)

You can also download Class 10 Maths NCERT Solution to help you to revise
complete syllabus and score more marks in your examinations.

Procedure

1. Divide the spherical plastic ball into two hemispherical portion with the help of a
cutter.
2. Fix a pin at the top most point of the hemisphere.
3. Take a roll of thread and wind it closely on the curved surface of the hemisphere
completely in the form of spiral starting with the pin on the surface of the
hemisphere
4. Take another roll of thread and wind it completely along the curved surface of the
cylinder in the form of a spiral.
5. Unwind the threads from the hemisphere and cylinder.