RBSE Solutions Class 6 Maths Chapter 10 Understanding Three Dimensional Shapes Exercise 10.1

Question 1. Identify the picture given below and name each of them.
(i)
(ii)
(iii)
(iv)
(v)
Answer:
(i) The first picture shows a **Cone**. Cones have a flat circular base and a single vertex at the top.
(ii) The second picture shows a **Sphere**. Spheres are perfectly round 3D objects, like a ball.
(iii) The third picture shows a **Cylinder**. Cylinders have two parallel circular bases and a curved surface connecting them.
(iv) The fourth picture shows a **Cube**. A cube has six square faces, all of equal size.
(v) The fifth picture shows a **Cuboid**. A cuboid has six rectangular faces, where opposite faces are identical.
In simple words: The pictures show different 3D shapes: a cone, a sphere, a cylinder, a cube, and a cuboid. Each has its own unique features.

🎯 Exam Tip: Remember the key features of each 3D shape, like the number of faces, edges, and vertices, as this helps in identification.

Question 2. Think and write
(i) Name of any two spherical fruits.
(ii) Name of two solid shapes made of fresh a sedish.
(iii) Name any two cylindrical shapes used in kitchen.
Answer:
(i) Two spherical fruits are **Apple** and **Orange**. They are round, like a sphere.
(ii) Two solid shapes made of fresh produce can be a **Carrot** (cone-like) and a **Cucumber** (cylinder-like). Fresh vegetables often have distinct 3D shapes.
(iii) Two cylindrical shapes used in the kitchen are a **Drinking Glass** and a **Water Bottle**. These objects are common examples of cylinders in daily life.
In simple words: Spherical fruits are round like an apple. Vegetables like carrots can be cone-shaped, and cucumbers are cylinder-shaped. In the kitchen, a glass and a water bottle are good examples of cylinders.

🎯 Exam Tip: Always think about everyday objects around you when identifying shapes, as it makes the concept easier to understand and remember.

Question 3. Say True/False :
(i) A cube and cuboid have 6 faces.
(ii) All edges of a cuboid are equal.
(iii) If the lid of a cylindrical box is removed, the box is left with a circular face and a cylindrical face.
(iv) Both the bases of a cone are circular.
(v) A cube can be obtained by cutting a cuboid through its edges.
(vi) Bangles are circular in shapes.
Answer:
(i) **True**. Both a cube and a cuboid have 6 faces, which are the flat surfaces.
(ii) **False**. Only the opposite edges of a cuboid are equal; all edges are equal only if it is a cube.
(iii) **True**. A cylinder has two circular bases and one curved side; removing a lid leaves one circular base and the curved surface.
(iv) **False**. A cone has only one circular base and a pointed top, not two bases.
(v) **True**. A cube is a special type of cuboid where all its edges are equal in length, so it can be considered a specific cut or type of cuboid.
(vi) **False**. Bangles are circular, which is a 2D shape, but the question implies they are 3D shapes or have a 3D property. While they have a 3D presence, "circular" is often used for 2D. However, if interpreted as a thin ring, they are not typically described as a 3D solid shape like a sphere or cylinder in this context.
In simple words: Cubes and cuboids have 6 faces. Not all edges of a cuboid are the same length. A cone has only one round bottom, not two. Bangles are flat circles, not 3D shapes.

🎯 Exam Tip: Understand the precise definitions of geometric terms like faces, edges, and vertices for each shape to answer true/false questions accurately.

Question 4. Write down the names of the faces, edges and vertices of the cuboid given below. Answer:
The cuboid shown has the following:
**Vertices:** P, Q, R, S, J, K, L, M. (These are the corners of the cuboid.)
**Edges:**
* Bottom edges: PQ, QK, KJ, JP
* Top edges: SR, RL, LM, MS
* Vertical edges: PS, QR, KL, JM
(Edges are the lines where two faces meet.)
**Faces:**
* Front face: PQRS
* Back face: JKLM
* Top face: SRML
* Bottom face: PQKJ
* Left face: PSMJ
* Right face: QRKL
(Faces are the flat surfaces of the cuboid.)
In simple words: A cuboid has corners called vertices. It has straight lines called edges. It has flat surfaces called faces. We have listed all of them for the cuboid shown in the picture.

🎯 Exam Tip: When listing vertices, edges, and faces, ensure you name them in a logical order to avoid missing any. Use the given labels carefully.