EDGE
Definition Of Edge
Edges are the intersection of faces in a three-dimensional figure.
Example of Edge
In the cube shown, the red line segment is the intersection of the faces A and B of the cube.
Video Examples:Edge-ucation: Vedic Maths: Trick for Multiplication of 2-Digit Nos
Solved Example on Edge
Ques: How many edges does a cube have?
Choices:
A. 14
B. 12
C. 10
D. 6
Corrected Answer: B
Solution:
Step 1: A cube has two square bases and four square faces joining the two bases.
Step 2: So, the number of edges of a cube = number of edges of the two bases + number of edges joining the bases.
Step 3: = (2 × 4) + 4 = 8 + 4 = 12
Step 4: So, a cube has 12 congruent edges.
Quick Summary
- Edges are formed where faces meet.
- Cubes have 12 edges.
- Edges are line segments.
🍎 Teacher Insights
Use physical models to demonstrate edges. Have students count edges on different shapes.🎓 Prerequisites
- Faces of 3D shapes
- Basic geometric shapes (cube, prism)
Check Your Knowledge
Q1: How many edges does a cube have?
Q2: An edge is the intersection of two what?
Frequently Asked Questions
Q: What is the difference between an edge and a face?
A: A face is a flat surface of a 3D shape, while an edge is a line segment where two faces meet.
Q: Do all 3D shapes have edges?
A: No, curved shapes like spheres do not have edges.