Radians to Degrees
Radians to degrees is a form of conversion used to convert the measurement of angles in geometry. To measure an angle, there are two different measuring systems. The two units used to measure an angle are radians and degrees. The unit radians is used mostly in the concept of trigonometry. The measure of angles can be converted from radians to degrees using a formula. To understand this formula and conversion of radians to degrees, we will understand the meaning of each unit of angle. We will also see the conversion table for radians to degrees in this article.
1. | Radians to Degrees Conversion |
2. | Radians to Degrees Formula |
3. | How to Convert Radians to Degrees? |
4. | Radians to Degrees Conversion Table |
5. | FAQs on Radians to Degrees |
Radians to Degrees Conversion
There are two different units used to measure an angle: radians and degrees. Hence, it is important for us to be proficient in the conversion of units of angle, that is radians to degrees and degrees to radians. When we take the radius of a circle and revolve it, we start constructing an angle that can be measured in radians or degrees. Let us see what each unit of angle means and how to measure the angle.
Radians
When we rotate the radius completely around the circle, it completes one rotation. The angle subtended at the center of the circle by the radius after one complete rotation is 2π radians. The angle in radians subtended by the radius at the center of the circle is the ratio of the length of the arc to the length of the radius. When the length of the arc becomes equal to the length of the radius, the angle subtended at the center becomes 1 radian. We denote the unit radian as rad. Radians is the SI unit of measuring angles.
Degrees
Angles are measured in degrees. One revolution is divided into 360 equal parts and each part is called a degree. The angle subtended at the center of the circle after one complete rotation of the radius is 360°. The symbol for degrees is denoted by '°'. Degrees is not an SI unit to measure angles but it is an accepted unit to measure. Hence, while solving problems, it is preferred to convert the unit of angle from radians to degrees to understand it better. The instrument used to measure an angle in degrees is a protractor.
Comparing the measures of the angle for a complete rotation, we observe,
- 360 Degrees = 2π Radians
- 180 Degrees = π Radians
Radians to Degrees Formula
The radians to degrees formula is used to convert radians to degrees. To convert radians to degrees we need to multiply the radians by 180°/π radians. When we measure angles we use two types of units: degrees and radians, 1 degree is written as 1°. And 1 radian is written as 1 (or) 1c i.e. if there is no unit after the measure of an angle, it means that it is in radians. One rotation in a circle is divided into 360 equal parts and each part is called a degree. One complete counterclockwise rotation in radians is 2π and in degrees, it is 360°. Thus, degree measure and radian measure are related. The formula to convert an angle in radians to degrees is:
Angle in Radians × 180°/π = Angle in Degrees
Derivation of Radians to Degrees Formula
One complete rotation around a circle gives 2π radians which is equivalent to 360°. Therefore, we have 2π radians = 360°. Now, to derive the formula for the conversion of radians to degrees, we will simplify this equation.
2π radians = 360°
π radians = 360°/2
π radians = 180°
1 radian = 180°/π
Hence the angle in degrees is obtained by multiplying the angle in radians by 180°/π. i.e.,
Angle in Radians × 180°/π = Angle in Degrees
Hence, the radians to degrees formula has been derived.
Therefore, to convert radians to degrees, use this formula = Radian measure × (180°/π). The final unit of measure will be (°). 1 rad equals 57.296°.
How to Convert Radians to Degrees?
Radians and degrees are the two units to measure angles. 2π radians is equivalent to 360° that is obtained after one complete revolution of a circle. The conversion of radians to degrees can be done using the formula 'Angle in Radians × 180°/π = Angle in Degrees'. Any angle given in radians can be converted to degrees using the steps given below,
- Note down the measure of the angle given in radians.
- We know, 1 radian = 180°/π. So, to convert the angle given in radians to degrees we multiply it with 180°/π.
Angle in Degrees = Angle in Radians × 180°/π - Simplify the values and express the answer in degrees(°).
Let us understand this with the help of an example.
Consider an angle π / 6 radians. Now, we need to convert the radians to degrees for this angle using the formula of conversion.
(π / 6) × (180°/π) = (Angle in Degrees)
Angle in Degrees = 180°/6 = 30°
Hence, π / 6 radians is equal to 30°.
Radians to Degrees Conversion Table
Now, let us collate the conversion of specific angles from radians to degrees which are more frequently used while solving problems. The below-given table shows the radian values for the corresponding angle measures in degrees:
Radians to Degrees Chart
We can also refer to the following radians to degrees chart to see the measure of any angle in degrees with respect to its measure in radians. We know that for a unit circle, the circumference will be equal to 2π, which is similar to rotating 360º as shown below.
☛Important Notes on Radians to Degrees
Here is a list of a few important points that should be kept in mind while converting radians to degrees :
- Angles are measured using two basic units: degrees and radians.
- One complete counterclockwise revolution is equal to 2π rad in radians.
- 1° equals 0.017453 radians and 1 rad equals 57.2958°.
- To convert an angle from radians to degrees, we multiply it by 180°/π.
- To convert an angle from degrees to radians, we multiply it by π/180°.
☛Related Topics
Checkout few more interesting topics closely related to radians to degrees conversion.
Radians to Degrees Examples
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Example 1: Convert the angle π/5 rad into degrees using the radians to degrees formula.
Solution: The formula to convert radians to degrees is:
Angle in Radians × 180°/π = Angle in Degrees
(π/5) × (180°/π )= Angle in Degrees
Angle in degrees = 180°/5
Angle in degrees = 36°
Hence, π/5 rad is equal to 36° using the radians to degrees formula.
Answer: π/5 rad = 36°
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Example 2: In a circle with center O, points A and B lie on the circle. ∠AOB has a measure of π/4 rad. Convert ∠AOB's angle measure from radians to degrees.
Solution: Given: ∠AOB = π/4 rad
We need to convert π/4 rad to degrees using the radians to degrees formula.
The formula required is: Angle in radians × 180°/π = Angle in degrees
π/4 rad × (180°/π ) = (Angle in degrees)
Angle in degrees = 180°/4
Angle in degrees = 45°
Hence, the measure of ∠AOB is equal to 45° in degrees.
Answer: ∠AOB = 45°
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Example 3: Amy's mother gave her (1/5)th of a circular cake and asked her about the angle subtended by the slice at the center of the cake. Can you help Amy determine the angle of the slice in radians and degrees?
Solution: The portion of cake Amy got = (1/5)th of the complete cake. Since the shape of the cake is circular, and the angle for a complete circle = 360°, thus we can conclude that:
Angle for the complete cake = 2π rad
The angle for the (1/5)th slice = 2π/5 rad
We know,
The value of this angle in degrees = angle in radians × (180°/π)
= (2π/5) × (180°/π) = 72°
Thus, the angle of Amy's slice in radians is 2π/5 rad, and when it is converted from radians to degrees, its measure is 72°.
Answer: Amy's slice in radians is 2π/5 rad and in degrees, it is 72°.
FAQs on Radians to Degrees
What Is Meant by the Conversion of Radians to Degrees in Geometry?
There are two units to measure angles in geometry, that is, radians and degrees. Radians is an SI unit to measure angles. One complete revolution of a circle equals 2π radians which are equivalent to 360° in degrees. Hence, 2π radians = 360° which implies 1 radian = (180°/π) degrees. Therefore, when the unit of angles is converted from radians to degrees using the formula, it is called the conversion of radians to degrees.
How To Convert Radians to Degrees?
The conversion of measure of an angle from radians to degrees can be done using the following formula: Angle in Radians × 180°/π = Angle in Degrees. For example, consider an angle π/9 rad. Now, using the radians to degrees formula, we have π/9 rad × 180°/π = (Angle in Degrees).
Angle in degrees = 180°/9 = 20°
Hence, using the formula, π/9 rad is equal to 20°
What Is the Formula To Convert Radians to Degrees?
We know that 2π radians is equal to 360° in degrees, that is, 2π radians = 360°. Simplifying this equation, we can obtain the formula to convert radians to degrees.
2π radians = 360°
1 radian = 360°/2π
1 radian = 180°/π
Hence, the required formula is Angle in Radians × 180°/π = Angle in Degrees
What Is the Difference Between Radians and Degrees?
Radians and degrees are both units to measure angles. Radian is an SI unit whereas degree is not but it is an accepted unit to measure angles. Radians measure angles by distance traveled whereas degrees measure angles by tilting.
What Is a Radians to Degrees Calculator Used For?
Radians to Degrees Calculator is an online tool that helps to convert radians to degrees for a given value. It helps you to convert radians to degrees in a few seconds. To convert an angle given in radians to degrees, we just need to multiply the angle by 180° / π.
What Is the Radian of 1 Degree?
One complete revolution of a circle is equal to 2π radians which is equivalent to 360°, therefore, we have the equation:
2π rad = 360°
1° = 2π/360 rad
1° = π/180 rad
Hence, 1 degree is equal to π/180 radians.
Which Expression Converts pi/4 Radians to Degrees?
Using radians to degrees formula, Degrees = Radians × 180 / π
Y° = (180/π) × π/4
Y°= 45 Degrees
How do You Convert Radians to Degrees Minutes and Seconds?
To convert radians to degrees, we divide by π and then multiply by 180. The fractions of a degree can be converted to minutes by multiplying the fraction by 60 to get the number of minutes. Similarly, any fraction of minutes remaining will be multiplied by 60 to get the number of seconds.
Can we Convert Negative Radian to Degree by Using the Radian to Degree Formula?
Yes, we can convert negative radian to a degree using the radian to degree formula. The formula is Degrees = Radians × 180 / π and it can be used for both positive and negative values.
Which Expression Converts 8π Radians to Degrees?
Using radians to degrees formula, Degrees = Radians × 180 / π
Z° = (180/π) × 8π
Z°= 1440 Degrees
How to Convert 6π to Degrees Using the Radian to Degree Formula?
Using radians to degrees formula, Degrees = Radians × 180 / π
X° = (180/π) × 6π
X°= 180 × 6
X°= 1080°
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