Which geometrical instrument used to mark off equal lengths but not to...
Compasses
Compasses are a geometrical instrument that is used to mark off equal lengths but not to measure them. It is commonly used in geometry for drawing arcs and circles. The instrument consists of two arms, one of which holds a pencil or pen while the other holds a pointed end that serves as a pivot point.
Marking off equal lengths
Compasses are used to mark off equal lengths by adjusting the distance between the two arms. The pointed end of the compass is placed at one end of the length to be marked, and the pencil or pen is used to mark off the same distance at the other end. This is useful for drawing regular polygons, where all sides must be of equal length.
Drawing arcs and circles
Compasses are also used for drawing arcs and circles. To draw a circle, the pointed end of the compass is placed at the center of the circle, and the pencil or pen is used to draw the circumference of the circle. To draw an arc, the pointed end is placed at one end of the arc, and the pencil or pen is used to draw the rest of the arc by rotating the compass around the pivot point.
Conclusion
Compasses are a versatile geometrical instrument that is used in many areas of mathematics and engineering. They are particularly useful for marking off equal lengths and for drawing arcs and circles, which are important in many geometric constructions.
Which geometrical instrument used to mark off equal lengths but not to...
Beacuse question is saying that not to measure them. We cannot use it to measure and moreover it is saying that 'draw arcs and circles'. So, the correct option is (A).
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