Question

1. A String of length 155 mm is
wound round a circle of radius 20
mm. Draw the path traced by the end
of the string. Also draw a tangent
and normal to a point on the curve.​

Answer 1

The tangent and normal to a point on the curve is given below.

Explanation:

• The tangent can be drawn as follow.
• First of all, draw a line 12-P that is tangent to 12.
• Now divide the line into 12 parts of equal length with a distance of L = πd
• Here "d" the diameter of the circle.
• Follow this pattern for the rest of the tangents and in the end, the involute will lie close to 12.