###### Asked in GeometryMath and ArithmeticAlgebra

# What instrument measures angles?

## Answer

###### Wiki User

###### November 04, 2017 5:02AM

A protractor, compass, speed square, goniometer, theodolites, sextant, or angle finder can be used to measure angles.

A protractor is a circular or semi circular instrument for measuring angles and some have existed from ancient times. A half circular protractor is marked for 180 degrees and a full circle for 360 degrees. Protractors usually have two sets of numbers going in opposite directions, so be careful which side you use. When in doubt you should ask yourself is the angle greater or smaller that 90 degrees.

An inclinometer measures the slope (aka grade or "incline") on mountain roads and trails.

Practice lining up and reading a protractor while you measure a set of angles in this fun learning activity. The angles may range from 0Â° to 180Â°. The interactive protractor is already lined up with the vertex of each angle but you will have to rotate the protractor into proper position. The margin of error is only 1Â° and you must report measurement to the nearest whole number.

A **protractor** measures angles whereas a
**compass** draws angles.

The typical protractor is 180 degrees. Protractors can also be circular and measure up to a full 360 degrees. Other methods of measuring angles include using a compass, and length measuring devices (rulers, tape measures, etc.) combined with trigonometry. Estimated angle measures can also use "devices." For example, the corner of a page can tell you if an angle is greater than or less than 90 degrees.

Navigators in the old days would use a sextant for measuring
angles. In more recent times they used a transit. A quadrant is yet
another tool for measuring the angle between the horizon and
heavenly bodies, also useful for navigation.

A protractor can be used to measure an angle.

###### Wiki User

###### October 20, 2017 5:57PM

It is a protractor.

###### Wiki User

###### October 20, 2017 5:21PM

A protractor is an instrument used to measure an
angle.

###### Wiki User

###### October 20, 2017 5:00PM

The instrument is a protractor.