a hollow garden roller if 42 cm diameter and length 147 cm is made of

1.	a hollow garden roller if 42 cm diameter and length 147 cm is made of cast iron of 2cm thickness. the volume of the iron used in the roller
Answer» Given data :- A HOLLOW garden ROLLER if 42 CM diameter and length 147 cm is made of cast iron of 2cm thickness. Here, → Diameter of roller ( d ) = 42 cm → Height of roller ( h ) = 147 cm → Thickness of iron ( t ) = 2 cm Solution :- To find the volume of the iron used in the roller . {From given} → Radius of roller ( R ) = ½ × d → Radius of roller ( R ) = ½ × 42 → Radius of roller ( R ) = 21 cm Here, radius of roller without thickness of iron {which is used in roller}. → radius of roller ( r ) = R - t → radius of roller ( r ) = 21 - 2 → radius of roller ( r ) = 19 cm Now we use formula to find volume of the iron used in the roller. → Volume of iron = π [ R² - r² ] h → Volume of iron = 22/7 [ (21)² - (19)² ] 147 → Volume of iron = 22/7 [ 441 - 361 ] 147 → Volume of iron = 22/7 × 80 × 147 → Volume of iron = 1760/7 × 147 → Volume of iron = 258720/7 → Volume of iron = 36960 cm³ Hence, the volume of the iron used in the roller is 36960 cm³.

a hollow garden roller if 42 cm diameter and length 147 cm is made of cast iron of 2cm thickness. the volume of the iron used in the roller

Answer»

A HOLLOW garden ROLLER if 42 CM diameter and length 147 cm is made of cast iron of 2cm thickness.

Here,

→ Diameter of roller ( d ) = 42 cm

→ Height of roller ( h ) = 147 cm

→ Thickness of iron ( t ) = 2 cm

To find the volume of the iron used in the roller .

{From given}

→ Radius of roller ( R ) = ½ × d

→ Radius of roller ( R ) = ½ × 42

→ Radius of roller ( R ) = 21 cm

Here, radius of roller without thickness of iron {which is used in roller}.

→ radius of roller ( r ) = R - t

→ radius of roller ( r ) = 21 - 2

→ radius of roller ( r ) = 19 cm

Now we use formula to find volume of the iron used in the roller.

→ Volume of iron = π [ R² - r² ] h

→ Volume of iron = 22/7 [ (21)² - (19)² ] 147

→ Volume of iron = 22/7 [ 441 - 361 ] 147

→ Volume of iron = 22/7 × 80 × 147

→ Volume of iron = 1760/7 × 147

→ Volume of iron = 258720/7

→ Volume of iron = 36960 cm³

Hence, the volume of the iron used in the roller is 36960 cm³.