Axis of Rotation
Definition of Axis of Rotation
Axis of Rotation is a line about which a threedimensional object is rotated in space.
More about Axis of Rotation

Axis of rotation of an object can be within the body or outside the body.
Examples of Axis of Rotation

The blue line in the above figure is the axis of rotation of the sphere.
Video Examples: Rotation of Axes: Part A
Solved Example on Axis of Rotation
Ques: Which of the following solid is formed when the given triangle is rotated about Xaxis?
Choices:
A. Figure 1B. Figure 2
C. Figure 3
D. Figure 4
Correct Answer: A
Solution:

Step 1: When a triangle is rotated about Xaxis, it forms a cone with its axis of symmetry as the same Xaxis.
Step 2: So, Figure 1 is formed when the given triangle is rotated along Xaxis.
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