Question

the radius of solid iron sphere is 8cm .Eight rings of iron plate of external radius 20/3cm and thickness 3cm are made by melting this sphere.Find the internal diameter of each ring​. plz help

Answer 1

Answer:

Now, it can be assumed that each ring of iron plate is a hollow cylindrical shell having internal radius 'r' cm and external radius 20/3 cm along with the  height 3 cm

Volume of each ring = π*(R² - r²)h

⇒ 3π*[(20/3)² - (r)²]

⇒ Volume of 8 rings = 8*3π[(20/3)² - (r)²]

⇒ 24π*[(20/3)² - (r)²]

Now, volume of sphere = Volume of 8 iron rings

⇒ 2145.52 = 24π[(20/3)² - (r)²]

⇒ 2145.52 = 24*22/7(400/9 - r²)

⇒ 2145.52*7 = 528(400/9 - r²)

⇒ 15018.64/528 = 400/9 - r²

⇒ r² = 44.44 - 28.44

⇒ r² = 16

⇒ r = √16

⇒ r = 4 cm

So, internal radius of the each ring is 4 cm.

Then, diameter = 4*2 

= 8 cm

Answer

Answer 2

Answer:

Therefore the internal radius is 4.

so diameter is 8 cm .

Step-by-step explanation:

See in the attachment .