The isometric projection of a circle is a
- ACircle
- BEllipseCorrect
- CParabola
- DHyperbola
Solution
Concept
Isometric projection of a circle
Formula
NONE
Step-by-step solution
1. An isometric projection foreshortens axes and distorts angles on the principal planes. 2. When a circle is projected isometrically, perpendicular diameters are unequally foreshortened. 3. As a result, the geometric representation of a circle in isometric projection becomes an ellipse. Answer: B
Explanation
When a circular object is viewed in isometric projection, its plane is inclined relative to the viewing plane, causing non-uniform foreshortening across its perpendicular diameters. This geometric distortion transforms the circular contour into a two-dimensional oval curve. As a result, the isometric projection of a circle always forms an ellipse.
Why the other options are wrong
A) A circle appears circular only in true orthographic views parallel to the plane. C) A parabola is an open conic section, not an isometric projection of a circle. D) A hyperbola is an open double-branched curve, not a projected circle.
Shortcut
Tilting a circle into 3D isometric view distorts it into an Ellipse.
Common mistake
Assuming that a circle retains its true circular shape in isometric projection rather than becoming an ellipse.
Correct answer: B) Ellipse