RBSE Class 8 Maths Notes Chapter 11 Mensuration

These comprehensive RBSE Class 8 Maths Notes Chapter 11 Mensuration will give a brief overview of all the concepts.

RBSE Class 8 Maths Chapter 11 Notes Mensuration

→ Area of a trapezium = \(\frac{1}{2}\) × (Sum of parallel sides) × height
= \(\frac{1}{2}\) × (Sum of parallel sides) × perpendicular distance between them.

→ Area of a rhombus = half the product of its diagonals.

→ Total surface area of a solid is the sum of the areas of its faces.

→ Total surface area of cuboid = 2(lb + bh + hl)
Where l = length, b = width/breadth, h = height

→ The lateral surface area of cuboid = 2(l + b)h
= Perimeter of base × height.

→ Total surface area of a cube = 6l², where l = edge (or side)

→ Lateral surface area of cube = 4(side)² = 4l²

→ Total surface area of a cylinder = 2πr (r + h)

→ Curved surface area of a cylinder = 2πrh

→ Amount of region occupied by a solid is called its volume.

→ Volume of cuboid = Length × Breadth × Height
= l × b × h

→ Volume of cube = (side)³ = a³

→ Volume of a right circular cylinder = (Area of base) × height
= πr² × h = πr²h

• 1 cm³ = 1 mL
• 1 L = 1000 cm³
• 1m³ = 1000 L
• 1 m² = cm²
• 1 km² = 10⁶ m² = 100 hectares
• 1 hectare = 100 acres = 10000 m²