Basic Details
Word: Radius
Part of Speech: Noun
Meaning: A straight line from the centre of a circle to its edge; the distance from the centre of a circle to the outside.
Synonyms: Arm, span
Antonyms: Diameter
Idioms and Phrases
- Within the radius: Refers to being within a certain distance from a point. Example: "There are five schools within a radius of two miles from my house."
- Expand your radius: To increase your area of influence or activity. Example: "When you move to a new city, it's good to expand your radius to meet new friends."
Usage Examples
Example 1: The radius of the circle is five centimetres, which means the distance from the centre to the edge is five centimetres.
Example 2: In geometry class, we learned how to calculate the area of a circle using its radius.
Example 3: To find the radius, you can measure the distance from the centre to any point on the edge of the circle.
Fun Fact
The word "radius" comes from Latin, where it means "ray" or "spoke." It was used to describe the spokes of a wheel radiating from the hub.
Famous Quote
"The knowledge of the world is only in the radius of a man's mind." - Ralph Waldo Emerson
Multiple Choice Questions (MCQs)
1. What does "radius" mean?
a) A type of triangle
b) A straight line from the centre of a circle to its edge
c) A measurement of length
d) A type of angle
Answer: b) A straight line from the centre of a circle to its edge
2. Which of these is a synonym of "radius"?
a) Diameter
b) Arm
c) Circle
d) Angle
Answer: b) Arm
3. What is the opposite of "radius"?
a) Triangle
b) Edge
c) Diameter
d) Length
Answer: c) Diameter
4. Which sentence uses "radius" correctly?
a) The radius of the circle can be seen in the painting.
b) The radius is too heavy to lift.
c) We have to adjust the radius for perfect symmetry in the design.
d) The radius of the tree was very tall.
Answer: c) We have to adjust the radius for perfect symmetry in the design.
5. Which idiom means to increase your area of activity?
a) Within the radius
b) Expand your radius
c) Hit the radius
d) Stay within the circle
Answer: b) Expand your radius
