explain the method of measuring the length of a curved line using divider
Answers
If the curved line is an arc of a circle:
1. Set the divider to a spacing that, from each end of the arc, will scribe an arc that crosses the arc you wish to measure, dividing it in two.
2. From each end of the arc, and again from the centre, and with the dividers set to a radius greater than before, strike arcs to form a cross each side of the arc you are measuring. Join the crosses above and below with a straight line. Project these lines below the arc, until they cross. This will be the centre of the circle the arc is part of.
3. Measure the radius of the arc. From that, calculate the perimeter of the circle it is part of.
4. Draw 2 radials from the centre to the outer ends of the arc. Measure the angle between them.
5. Divide the perimeter by 360, then multiply that result by the degrees in the angle measured.
That will be the length of the arc........
Length of a curved line={ No.of times}.
{Divider is based}.
{moved}.
Multiply×
distance between
the legs of
the divider
Additional+
length of the
remaining portion
of the line
For example= Distance between the legs of the divider =10 mm
No. of the times the divider is moved along the line =20
length of the over portion at the end of the line =3mm
Then length of the curved line =20× 10 mm+3mm
=203 mm=203
____ = 20.3 cm
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