Circles Circular Logic Quiz

1. If the diameter of a circle is 80 what is the radius?

40

160

180

The diameter of a circle is twice the length of its radius. Therefore, if the diameter is 80, the radius would be half of that, which is 40.

Explanation

The diameter of a circle is twice the length of its radius. Therefore, if the diameter is 80, the radius would be half of that, which is 40.

2. There can be more then one chord

True

False

The statement suggests that it is possible to have more than one chord. A chord is a line segment that connects two points on a curve. Since a curve can have multiple points, it is logical to conclude that there can be more than one chord. Therefore, the answer is true.

Explanation

The statement suggests that it is possible to have more than one chord. A chord is a line segment that connects two points on a curve. Since a curve can have multiple points, it is logical to conclude that there can be more than one chord. Therefore, the answer is true.

3. If the radius of a circle is 10 what is the diameter?

21

20

5

The diameter of a circle is twice the length of its radius. Therefore, if the radius of a circle is 10, the diameter would be 10 multiplied by 2, which equals 20.

Explanation

The diameter of a circle is twice the length of its radius. Therefore, if the radius of a circle is 10, the diameter would be 10 multiplied by 2, which equals 20.

4. If a radius is 8 the diameter is 4

True

False

The statement "If a radius is 8 the diameter is 4" is incorrect. The diameter of a circle is always twice the length of its radius. Therefore, if the radius is 8, the diameter would be 16, not 4.

Explanation

The statement "If a radius is 8 the diameter is 4" is incorrect. The diameter of a circle is always twice the length of its radius. Therefore, if the radius is 8, the diameter would be 16, not 4.

5. What do you call a line that connects 2 points on the circumference, that is not a diameter?

Diameter

Tangency line

Chord

A chord is a line that connects two points on the circumference of a circle, but it is not a diameter. Unlike a diameter, which passes through the center of the circle, a chord can be located anywhere on the circumference. Therefore, a chord is the correct term for a line that connects two points on the circumference of a circle, excluding the diameter.

Explanation

A chord is a line that connects two points on the circumference of a circle, but it is not a diameter. Unlike a diameter, which passes through the center of the circle, a chord can be located anywhere on the circumference. Therefore, a chord is the correct term for a line that connects two points on the circumference of a circle, excluding the diameter.

6. What do you call the point where the tangency line meets the circumference?

Point of tangency

Tangency point

None of the above

The point where the tangency line meets the circumference is referred to as the point of tangency. This is the exact location where the line touches the circumference of the circle. It is called the point of tangency because it is the point at which the line is tangent to the circle, meaning it touches the circle at only one point without intersecting it.

Explanation

The point where the tangency line meets the circumference is referred to as the point of tangency. This is the exact location where the line touches the circumference of the circle. It is called the point of tangency because it is the point at which the line is tangent to the circle, meaning it touches the circle at only one point without intersecting it.

7. A diameter is a chord

True

False

A diameter is a chord because a chord is a line segment that connects two points on a circle. A diameter is a special type of chord that passes through the center of the circle, dividing it into two equal halves. Therefore, every diameter is a chord, but not every chord is a diameter.

Explanation

A diameter is a chord because a chord is a line segment that connects two points on a circle. A diameter is a special type of chord that passes through the center of the circle, dividing it into two equal halves. Therefore, every diameter is a chord, but not every chord is a diameter.

8. There can be 2 points of tangency

True

False

The statement "There can be 2 points of tangency" is false. In geometry, a point of tangency is a point where a line or curve touches a circle or another curve at a single point. Two points of tangency would imply that the line or curve intersects the circle or curve at two different points, which contradicts the definition of tangency. Therefore, there can only be one point of tangency between a line or curve and a circle or another curve.

Explanation

The statement "There can be 2 points of tangency" is false. In geometry, a point of tangency is a point where a line or curve touches a circle or another curve at a single point. Two points of tangency would imply that the line or curve intersects the circle or curve at two different points, which contradicts the definition of tangency. Therefore, there can only be one point of tangency between a line or curve and a circle or another curve.