What is Cuboid - A Cuboid is a three-dimensional shape that looks like a rectangular box, with six faces, twelve edges, and eight vertices. It is also called a rectangular prism. All its faces are rectangles, and opposite faces are equal and parallel. This means the shape is balanced and uniform, making it easy to identify.
A cuboid is formed when rectangles are stacked together to create a 3D figure. Each face meets its neighboring faces at right angles, ensuring all edges and corners are well-defined. For instance, if you stack identical books on top of one another, they create a cuboid-like shape. An example of a cuboid in real life is a shoebox. The top and bottom of the box are larger rectangles, while the four sides form the remaining faces. The edges are the straight lines where two faces meet, and the corners where three edges come together are the vertices. [video width="1920" height="1080" mp4="https://www.pw.live/exams/wp-content/uploads/2024/12/Curious-Jr-Ad-3-1-1.mp4"][/video]Example: On the top face (ABCD), the diagonals are AC and BD . Similar diagonals can be drawn on the other five faces.
The length of a face diagonal can be calculated using the formula:Face Diagonal= √l 2 +b 2
Where l and b are the dimensions of the rectangle (length and breadth).TSA= 2(lb+bh+lh) square unit
The formula adds the area of the three pairs of opposite faces (length × breadth, breadth × height, and length × height) and multiplies it by 2 because each pair appears twice. Example: For a cuboid with l = 5 units, b = 3 units, h = 4 units l = 5 TSA = 2(5 × 3 + 3 × 4 + 5 × 4) = 2(15 +12 + 20) = 2(47) = 94 square units.Cuboid Formulas | |
Measure | Formula |
Lateral Surface Area (LSA) | 2h(l + b) |
Total Surface Area (TSA) | 2(lb + bh + hl) |
Volume of cuboid | lbh |
Perimeter of cuboid | 4(l + b + h) |
Face Diagonal | √l 2 +b 2 |
Space Diagonal | √l 2 + b 2 + h 2 |
Calculate the lateral and total surface area of a cuboid with dimensions 15 cm × 10 cm × 8 cm.
Solution: Given: Length (l) = 15 cm Breadth (b) = 10 cm Height (h) = 8 cm Lateral Surface Area (LSA): LSA= 2h(l+b) = 2h(l + b) = 2×8(15+10) =2×8×25 400 cm 2 Total Surface Area (TSA): TSA=2(lb+bh+hl) =2(15×10+10×8+8×15) =2(150+80+120) = 2×350=700 cm ² If the length and width of a cuboid are 9 inches and 12 inches, respectively, what is the face diagonal? Solution: Given:Related Articles | |
Area of Rectangle | Isosceles Triangle |
Composite Numbers | Differentiation |
Perimeter of Rectangle | Surface Area of Cylinder |