3D Shapes (Grade 2)
3D shapes (three-dimensional shapes) are solid objects that have length, breadth, and height. Unlike flat 2D shapes, you can hold 3D shapes in your hands.
In Class 2, children learn about common 3D shapes: cube, cuboid, cone, cylinder, and sphere. Each shape has specific faces, edges, and corners (vertices).
What is 3D Shapes (Grade 2) - Class 2 Maths (Shapes (Grade 2))?
A 3D shape is a solid shape with three dimensions: length, breadth, and height.
Parts of a 3D shape:
- Face: A flat or curved surface of the shape.
- Edge: The line where two faces meet.
- Corner (Vertex): The point where edges meet.
Properties of common 3D shapes:
| Shape | Faces | Edges | Corners | Real-life Example |
|---|---|---|---|---|
| Cube | 6 | 12 | 8 | Dice, Rubik’s cube |
| Cuboid | 6 | 12 | 8 | Brick, book, tiffin box |
| Cone | 2 (1 flat + 1 curved) | 1 | 1 | Ice cream cone, birthday cap |
| Cylinder | 3 (2 flat + 1 curved) | 2 | 0 | Bangle, pipe, can |
| Sphere | 1 (curved) | 0 | 0 | Ball, globe, orange |
Solved Examples
Example 1: Example 1: Identify a cube
Question: Aman picks up a dice. What 3D shape is it?
Think:
- A dice has 6 flat square faces
- All faces are the same size
- It is a cube
Answer: A dice is shaped like a cube.
Example 2: Example 2: Cuboid in real life
Question: Name 3 objects shaped like a cuboid.
Think:
- A cuboid has 6 rectangular faces
- Brick, eraser, cereal box are all cuboid-shaped
Answer: A brick, an eraser, and a cereal box are cuboids.
Example 3: Example 3: How many edges does a cube have?
Question: Count the edges of a cube.
Think:
- A cube has 6 faces
- Each face is a square with 4 edges
- But edges are shared between two faces
- Total edges = 12
Answer: A cube has 12 edges.
Example 4: Example 4: Sphere vs Circle
Question: How is a sphere different from a circle?
Think:
- A circle is a flat (2D) shape
- A sphere is a solid (3D) shape — like a ball
- A sphere has depth; a circle does not
Answer: A circle is flat (2D). A sphere is round and solid (3D). A ball is a sphere, not a circle.
Example 5: Example 5: Faces of a cylinder
Question: How many faces does a cylinder have?
Think:
- A cylinder has 2 flat circular faces (top and bottom)
- It also has 1 curved face (the side)
- Total = 3 faces
Answer: A cylinder has 3 faces (2 flat + 1 curved).
Example 6: Example 6: Cone properties
Question: How many corners does a cone have?
Think:
- A cone has a pointed tip at the top
- That tip is its only corner (vertex)
Answer: A cone has 1 corner (the pointed tip).
Example 7: Example 7: Sort objects by shape
Question: Sort these objects: cricket ball, matchbox, party hat, tin can, dice.
Think:
- Cricket ball → sphere
- Matchbox → cuboid
- Party hat → cone
- Tin can → cylinder
- Dice → cube
Answer: Sphere: ball. Cuboid: matchbox. Cone: party hat. Cylinder: tin can. Cube: dice.
Key Points to Remember
- 3D shapes are solid shapes with length, breadth, and height.
- They have faces (flat or curved surfaces), edges (where faces meet), and corners/vertices (where edges meet).
- A cube has 6 equal square faces, 12 edges, 8 corners.
- A sphere has 1 curved face, 0 edges, 0 corners.
- A cylinder has 2 flat faces + 1 curved face, 2 edges, 0 corners.
- Real objects like balls, boxes, and cans are 3D shapes.
Practice Problems
- How many faces does a cuboid have?
- Name an object shaped like a cone.
- Which 3D shape has 0 edges? (cube, sphere, or cylinder)
- How is a cube different from a cuboid?
- Find 3 objects at home shaped like a cylinder.
- How many corners does a sphere have?
Frequently Asked Questions
Q1. What is the difference between 2D and 3D shapes?
2D shapes are flat (length and breadth only) — like a circle drawn on paper. 3D shapes are solid (length, breadth, and height) — like a ball you can hold.
Q2. What is the difference between a cube and a cuboid?
A cube has 6 equal square faces. A cuboid has 6 rectangular faces, where opposite faces are equal but all faces are not necessarily squares.
Q3. Does a sphere have any flat faces?
No. A sphere has only 1 curved face. It has no flat faces, no edges, and no corners.
Q4. What is an edge?
An edge is the line where two faces of a 3D shape meet. A cube has 12 edges. Think of the lines on a dice.
Q5. Why does a cylinder have 0 corners?
Corners form where edges meet at a sharp point. A cylinder’s edges are circular (not straight), so they do not form sharp points.
Q6. Can a 3D shape have curved faces?
Yes. A sphere has 1 curved face. A cylinder has 1 curved face + 2 flat faces. A cone has 1 curved face + 1 flat face.
