Question

The instrument to measure an angle is a
(a) Ruler
(b) Protractor
(c) Divider
(d) Compasses

Answer 1

Hint: An angle is a measure of an inclination of a line with another line. Thus, we have to find that instrument with the help of which we can measure a particular angle. To do this, we will check each option one by one.

Complete step-by-step solution -
Before finding which instrument is used to measure an angle, we must first know what an angle is. An angle is the figure formed by the two rays called the sides of an angle, sharing a common endpoint, called the center of the angle. In other words, we can say that an angle is a measure of inclination of a line with another line. So, in the question, we have to find the instrument with which we can measure a particular angle. Thus we will check what each instrument given In the question does.
Option (a) Ruler: A ruler is an instrument which is either used to find the length of a line drawn or to draw a straight line of fixed length. It cannot be used to measure angles.
Option (b) Protractor: A protractor is an instrument which is generally divided into 180 equal parts and it is used for making and measuring angles.
Option (c) Divider: A divider is an instrument for measuring, transferring or making off distance. It cannot be used to measure angles.
Option (d) Compass: A compass is a technical drawing instrument that can be used for inscribing circles or arcs. They can also be used to measure distance but cannot be used for measuring angles.
Hence, option (b) is correct.

Note: The compass cannot be used to measure a particular angle but we can compare two given angles with the help of compass and we can determine which of the two angles is greater, which is smaller or are they equal.