Circumference of a Circle

Q.

Circumference of a circle is always-

1. more than three times of its diameter

2. three times of its diameter

3. less than three times of its diameter

4. three times of its radius

Q. Rahul divides a circular disc of radius 7 cm into two equal parts. What is the perimeter of each semi-circular disc?

1. 32 cm
2. 35 cm
3. 36 cm
4. 42 cm

Q. 24. The ratio of the area of circle with centre O and the area of the rectangle ABCD inscribed in it is π :\sqrt{}3 . E is a point on AB such that ∠ADE = ∠ODC. Find AE :AD.

Q.

What is the circumference of a circle with radius 2r units?

1. $\pi$r

2. 2$\pi$r

3. $\pi r^2$

4. 4$\pi r$

Q.

A car travels 0.99 km distance in which each wheel makes 450 complete revolutions. Find the radius of its wheel in m.

1. 0.45

2. 0.35

3. 0.55

4. 0.65

Q. A circle is inscribed in a right angled triangle of perimeter 7π. The ratio of numerical values of circumference of the circle and the area of the right angled triangle is?

Q.

If the circumference of a circle exceeds its diameter by 180 cm, then find its radius in cm.

1. 32

2. 36

3. 40

4. 42

Q. Three equal circles of unit radius touch each other . Then , the area of the circle circumscribing the three circles is

Q. Q. Three circles of radius 1 cm touch one another externally. Find the area of the circle circumscribing the circle.

Q.

What is the circumference of a circle with radius r and diameter d?

1. πr

2. πr²

3. πd

4. πd²

Q.

The circumference of a circle whose area is $81{\mathrm{\pi r}}^2$, is

1. $9\mathrm{\pi r}$

2. $18\mathrm{\pi r}$

3. $3\mathrm{\pi r}$

4. $81\mathrm{\pi r}$

Q. The circumference of the circle which has a diameter of 16 cm is .

1. $8\pi cm$
2. $16\pi cm$
3. $32\pi cm$
4. $48\pi cm$

Q. If the circumference of a circle is 110 cm, then its diameter is .

1. 40 cm
2. 20 cm
3. 30 cm
4. 35 cm

Q.

Circumference of circle with radius $\frac{1}{\pi }$ is 2 units.

1. False

2. True

Q. 5. 3 girls , Reshma , Salma and Mandeep r playing game in a circular park with radius 5m Distance between Reshma and Salma and between Salma and Mandeep is 6m each, What is the distance between Reshma and Mandeep?

Q. A wire is bent to form a circle of radius 7 cm. From the resulting shape, a chunk of the wire is cut off, and the wire cut off measures 4 cm in length. The length of the remaining wire is ___ cm

Q.

The circumference of a circular field is 528 cm. Then its radius is __________.

1. 56 cm

2. 72 cm

3. 42 cm

4. 84 cm

Q.

If the sum of the circumferences of two circles with radii $R_1$ and $R_2$ is equal to the circumference of a circle of Radius R then _________.

1. 

2. 

3. 

4. None of these

Q. Question 10
In the given figure, you see the frame of a lampshade. It is to be covered with a decorative cloth. The frame has a base diameter of 20 cm and height of 30 cm. a margin of 2.5 cm is to be given for folding it over the top and bottom of the frame. Find how much cloth is required for covering the lampshade. $[Assume\pi =\frac{22}{7}]$

Q. Question 9 (ii)
A brooch is made with silver wire in the form of a circle with diameter 35 mm. The wire is also used in making 5 diameters which divide the circle into 10 equal sectors as shown in Fig. 12.12. Find:
(ii) The area of each sector of the brooch.

Q.

Diameter of a circular park is $14m.$ Find its circumference. (Take $\pi =\frac{22}{7}$)

1. $23m$

2. $44m$

3. $43m$

4. $22m$

Q.

The area of the given figure is ___$c{m}^2$​. $(\text{Both the ends are semi-circular and}\pi =\frac{22}{7})$

Q. Perimeter of a circle is called its

1. circumference
2. area
3. diameter
4. none of these

Q. The perimeter of the given figure is:

1. 4.2 cm
2. 8.4 cm
3. 9.1 cm
4. 3.1 cm

Q. Calculate the length of the tape required to encircle a circular ring of radius 10 cm.

Q.

The length of the complete circle is called __ of the circle.

Q.

In the diagram, a square is drawn such that the diagonally opposite corners touch the Centre and the circumference of a circle whose radius is r. Find the area of the square.

1. $\frac{r^2}{4}$

2. $r^2$

3. $2r^2$

4. $\frac{r^2}{2}$

Q. If the difference between the circumference and the radius of a circle is $37cm$, then using $\pi =\frac{22}{7}$, the circumference (in cm) of the circle is:

1. $154$
2. $44$
3. $14$
4. $7$

Q. Raj cuts a disc with a radius of 7 cm into two equal parts. Calculate the entire perimeter.

1. 32 cm
2. 35 cm
3. 36 cm
4. 42 cm

Q.

What is the radius of the circle whose perimeter is equal to its area?

1. π units

2. 2 units

3. 0 units

4. 1 unit