Question

35 circular plates , each of radius 21 cm and thickness 2 cm are placed one above the other to form a three dimensional solid shape. Give the following
1. Name of the shape formed (1 mark)
2. Height of the shape formed (1 mark)
3. CSA or LSA of the shape formed (1.5 marks)
4. Volume of the shape formed (1.5 marks)
Take π= 22/7

Answer 1

Answer:

Solution:

Given,

A solid sphere of radius, R = 8 cm

With this sphere, we have to make spherical balls of radius r = 1 cm

Let’s assume that the number of balls made as n

Then, we know that

Volume of the sphere = 4/3 πr3

The volume of the solid sphere = sum of the volumes of n spherical balls.

n x 4/3 πr3 = 4/3 πR3

n x 4/3 π(1)3 = 4/3 π(8)3

n = 83 = 512

Therefore, 512 balls can be made of radius 1 cm each with a solid sphere of radius 8 cm.

Answer 2

Answer:

Solution:

Given,

A solid sphere of radius, R = 8 cm

With this sphere, we have to make spherical balls of radius r = 1 cm

Let’s assume that the number of balls made as n

Then, we know that

Volume of the sphere = 4/3 πr3

The volume of the solid sphere = sum of the volumes of n spherical balls.

n x 4/3 πr3 = 4/3 πR3

n x 4/3 π(1)3 = 4/3 π(8)3

n = 83 = 512

Therefore, 512 balls can be made of radius 1 cm each with a solid sphere of radius 8 cm.