Question

Half of a circle is called _____________________
7. Diameter is _______________ the radius
II. Tick the correct answer:
1. Two rays with the common end point makes an _____________________
a. angle b. ray c. parallel line d. perpendicular line
2. Any part of a circle is called an __________________
a. radius b. arc c. chord d. circumference
3. All the radii of a circle are __________________ in length.
a. parallel b. equal c. unequal d. perpendicular
4. The angle whose measure is exact 90° is called as _________________
a. Straight angle b. Right angle c. Obtuse angle d. Acute angle
5. The longest chord of the circle is ______________
a. Radius b. Diameter c. Arc d. Circumference
II. Solve:
1. Find the diameter of the circle whose radius is 8m.
2. Find the radius of the circle whose diameter is 18cm.
3. Construct a circle of radius 4cm and name the following.
a)Centre of the circle

Answer 1

★ Required Answers ::

❶ Half of circle is called $\boxed{\bf{semi\:circle}}$

❷ Diameter is $\boxed{\bf{twice}}$ the radius.

❸ Two rays with the common end point makes an $\boxed{\bf{angle}}$

❹ Any part of a circumference of circle is called an $\boxed{\bf{arc}}$

❺ All the radii of a circle are $\boxed{\bf{equal}}$ in length.

❻ The angle whose measure is exact 90° is called $\boxed{\bf{right\:angle}}$

❼ The longest chord of the circle is $\boxed{\bf{diameter}}$

❽ Find the diameter of the circle whose radius is 8m.

We know that,

• Diameter is twice the radius.

i.e,

$\large{\boxed{\sf{Diameter = Radius\:\times\:2}}}$

According to the question by using the formula we get,

⇒ $\sf Diameter = (8\:\times\:2)m$

➠ $\bf\red{Diameter = 16m}$

❾ Find the radius of the circle whose diameter is 18cm.

Again we know that,

• Diameter is twice the radius. So, radius is half the diameter

i.e,

$\large{\boxed{\sf{Radius = \dfrac{Diameter}{2}}}}$

According to the question by using the formula we get,

⇒ $\sf Radius = {\cancel{\dfrac{18}{2}}}$

➠ $\bf\purple{Radius = 9cm}$

❿ Construct a circle of radius 4cm and name the following.

• (a) Centre of the circle $\leadsto\:\boxed{\bf{O}}$

[Note :: For construction & steps of construction please refer the attachment]

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬