# A solid iron pole consists of a cylinder of height 220 cm and base diameter 24 cm, which is surmounted by another cylinder of height 60 cm and radius 8 cm. Find the mass of the pole, given that 1 cm^{3} of iron has approximately 8 g mass. (Use π = 3.14)

**Solution:**

The figure drawn below is to visualize the iron pole.

We can see that,

Volume of the solid iron pole = volume of larger cylinder + volume of smaller cylinder

Mass of iron in the pole = 8 g × volume of the solid iron pole in cm^{3}

We will find the volume of the solid by using formula;

Volume of the cylinder = πr^{2}h where r and h are the radius and height of the cylinder respectively

Radius of larger cylinder, R = 24 cm/2 = 12 cm

Height of larger cylinder, H = 220 cm

Radius of smaller cylinder, r = 8 cm

Height of smaller cylinder, h = 60 cm

Volume of the solid iron pole = volume of larger cylinder + volume of smaller cylinder

= πR^{2}H + πr^{2}h

= π(12 cm × 12 cm × 220 cm + 8 cm × 8 cm × 60 cm)

= 3.14 × (31680 cm^{3} + 3840 cm^{3})

= 3.14 × 35520 cm^{3}

= 111532.8 cm^{3}

Mass of 1 cm^{3} iron is 8 g

Mass of iron in the pole = 8 g × volume of the solid iron pole

= 8 g × 111532.8

= 892262.4 g

= 892262.4/1000 kg

= 892.2624 kg

Thus, the mass of iron in the pole is 892.26 kg.

**☛ Check: **NCERT Solutions Class 10 Maths Chapter 13

**Video Solution:**

## A solid iron pole consists of a cylinder of height 220 cm and base diameter 24 cm, which is surmounted by another cylinder of height 60 cm and radius 8 cm. Find the mass of the pole, given that 1 cm^{3} of iron has approximately 8 g mass. (Use π = 3.14)

NCERT Solutions for Class 10 Maths Chapter 13 Exercise 13.2 Question 6

**Summary:**

A solid iron pole consists of a cylinder of height 220 cm and base diameter 24 cm, which is surmounted by another cylinder of height 60 cm and radius 8 cm. The mass of the pole, given that 1 cm^{3} of iron has approximately 8 g mass is 892.26 kg.

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