Which of the following belongs to a projected aid ?

Question

Accepted Answer

Instructional media in teaching methodology are broadly classified into projected and non-projected aids based on their technical delivery mechanisms. Projected visual aids require a light source, optical lenses, or electronic systems to project static or dynamic images onto a screen or surface, allowing a magnified view for large groups. These systems bridge abstract thinking by enlarging diagrams, texts, or physical objects, thereby enhancing spatial and conceptual clarity. In contrast, non-projected media present educational content directly without any mechanical or illumination assistance.

Correct Option (Option 3):
An epidiascope is a classic projected visual aid that functions as both an episcope (for projecting opaque objects like pages, photographs, or specimens via reflected light) and a diascope (for projecting transparent materials like slides). It uses a powerful light source and mirrors to cast an enlarged real image onto an external screen, ensuring that a whole classroom can view details of concrete items together.

Incorrect Option (Option 1):
A blackboard is a traditional, two-dimensional non-projected visual aid. It serves as a passive writing surface that relies entirely on the instructor using chalk to draw or write. It does not contain any integrated lens, lamp, or magnification system to project content onto an independent screen. Therefore, it cannot be categorized under modern projected instructional systems.

Incorrect Option (Option 2):
A diorama is a three-dimensional non-projected visual aid representing a miniature scenic display. It showcases a realistic model or three-dimensional figures against a painted background to recreate historical events or natural habitats. Because it requires no electrical projection apparatus to magnify or project an image onto a distinct wall, it remains a purely static, physical exhibit.

Incorrect Option (Option 4):
A globe is a three-dimensional non-projected geographic model that provides a realistic representation of the Earth. It is an interactive tool handled physically by students and instructors to understand scale, rotation, and distribution of continents. Since it is viewed directly in its physical form without the use of an optical projection medium, it falls strictly under non-projected spatial aids.