Reflection

Important Questions

Chapter 12 of ICSE Class 10 Mathematics, titled "Reflection," delves into the fascinating world of geometry and transformations. This chapter introduces students to the concept of reflection, a fundamental geometric operation that involves flipping or mirroring objects across a line known as the "mirror line" or "axis of reflection." Here's an introductory overview of reflection questions class 10 ICSE.

Tables of Content

The chapter reflection of class 10 ICSE Mathematics, titled "Reflection," is a captivating exploration of geometry and symmetry. In this chapter, students delve into the intriguing concept of reflection, a fundamental geometric transformation that involves mirroring objects across a line, known as the "mirror line" or "axis of reflection."

Here's an introductory overview of Chapter 12 - "Reflection":

"In ICSE Class 10 Mathematics, Chapter 12, 'Reflection,' invites students into the captivating realm of symmetry and geometric transformations. Reflection, the core theme of this chapter, unveils the beauty of symmetry by showcasing how objects can be mirrored or flipped across a line.

Reflection, as we study in the chapter reflection of class 10 ICSE in the context of geometry and mathematics, is a fundamental transformation that involves flipping or mirroring an object or figure across a specific line called the "mirror line" or "axis of reflection." The result of this transformation is a new figure that is a precise copy of the original but is oriented in the opposite direction.**Key points about reflection:****Mirror Line:** The mirror line is the central axis or line across which the reflection occurs. It serves as the axis of symmetry, dividing the figure into two equal and mirror-image halves.**Symmetry:** Reflection is a transformation that preserves symmetry. The original figure and its reflection are symmetric with respect to the mirror line. This means that corresponding points on both sides of the mirror line are equidistant from it.

**Orientation Change:** During reflection, the orientation of the figure changes. For example, if you have a letter 'E' and you reflect it horizontally, you get a backward 'E.'

(b) a = – 3, b = – 2

(c) a = 5, b = – 2

(d) a = 2, b = 5

**Ans**. (b) a = – 3, b = – 2

**Explanation:**Co-ordinates of P′(3, –2).

∴ a = 3, b = –2.

(b) (4, 3)

(c) (6, 3)

(d) (8, 3)

**Ans**. (c) (6, 3)

**Explanation:**Globalisation has created conditions for increased job opportunities.

(i) A´, B´, C´,

(ii) A´´, B´´, C´´.

**Explanation:**(i) A´ → (1, – 2),

B´ → (4, – 4),

C´ → (3, – 7).

(ii) A´´ → (– 1, 2),

B´´ → (– 4, 4),

C´´ → (– 3, 7).

(i) An isosceles right-angled triangle is reflected in its hypotenuse.

(ii) A right-angled triangle is reflected in its hypotenuse.

(iii) An isosceles triangle is reflected in its unequal side.

(iv) A scalene triangle is reflected in its greatest side.

**Explanation:**

Write down the coordinates of (i) A′, B′, C′, (ii) A′′, B′′, C′′, (iii) Assign the special name to the quadrilateral BCC′′B′′ and find its area.

**Explanation:** Given, vertices of triangles are A(1,2), B (4,4), C (3,7).

(a) Coordinates A(1,2), B (4,4), C (3,7).

(b) Coordinates A”=(- 1,2), B”= (-4,4), C”= (3,7).

(c) BCC”B” is a trapezium

Area of trapezium = \(\dfrac{1}{2}\) (Sum of parallel sides) × height

= \(\dfrac{1}{2}\) (BB”+CC”) ×MN

= \(\dfrac{1}{2}\) (8+6)×3

= \(\dfrac{14}{2}\) ×3

= 21 sq. units.

In conclusion, the study of reflection of class 10 ICSE offers students a fascinating exploration of symmetry and geometric transformations. This chapter delves into the fundamental concept of reflecting objects and figures across a mirror line, unveiling the beauty of symmetry and its practical applications in various fields.

Throughout this chapter, students have learned to identify mirror lines, understand the principles governing reflection, and apply these concepts to geometric shapes. Reflection not only enhances students' appreciation of symmetry but also sharpens their problem-solving skills. If you're looking to enhance your skills through additional practice and gain a deeper understanding of the topics covered in the chapter, oswal.io offers an extensive collection of reflection questions class 10 ICSE to support your quest for a more profound comprehension of the concepts.

**Ans: **Reflection is a geometric transformation that involves mirroring an object or figure across a line, called the mirror line, resulting in a symmetrical image.

**Ans: **The mirror line is the central line across which the reflection occurs, serving as the axis of symmetry.

**Ans: **During reflection, the orientation of the figure changes. It becomes a mirror image of the original across the mirror line.

**Ans:** Reflection is denoted by "R" followed by the mirror line. For example, "R(x-axis)" represents reflection across the x-axis.

**Ans:** A figure has reflection symmetry if it can be divided into two identical halves when reflected across a mirror line.