The diameter of a cylinder is 14 cm and its height is 10 cm. Find its volume. Use π = $\frac{22}{7}$ .

Class 8MensurationMensuration

Step-by-Step Solution

Radius

r

= diameter ÷ 2 = 14 ÷ 2 = 7 cm.

V

= π

r^{2}

h = \frac{22}{7} \times 49 \times 10 = 22 \times 7 \times 10 = 1540 cm^{3}

Answer: D) 1540

A cylinder is a circle stacked vertically. Two measurements: radius

r

and height

h

.

**Curved surface area (CSA) = 2π

r h

** (imagine 'unrolling' the curved surface — it becomes a rectangle of width 2π

r

and height h).

**Total surface area (TSA) = 2π

r^{2} + 2

r h = 2

r (r + h)

** (curved surface + two circular ends).

**Volume = π

r^{2}

h

** (area of circular base × height).

Use π = 22/7 when

r

is a multiple of 7; otherwise π ≈ 3.14.

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