Circumference of Circle

Q. The diameter of a circle is 7cm, then the radius of the circle is .

1. 7cm
2. 3.5cm
3. 14cm
4. 4.5cm

Q. Radius of a circle is 7 cm, then find the perimeter of circle given (Use $\pi$ = $\frac{22}{7}$).

1. 14 cm
2. 22 cm
3. 28 cm
4. 44 cm

Q. Find the length of the arc which subtends ${120}^o$ angle at centre of circle whose radius is 21 cm.

1. 11 cm
2. 22 cm
3. 44 cm
4. 88 cm

Q. The radius of the wheel is 49 cm. Find the number of revolutions that the wheel makes to cover a distance of 6160 cm.

1. 5
2. 10
3. 20
4. 40

Q. If the perimeter of a semi circle is 216 cm, what is its diameter?

1. 
   84 cm
2. 
   82 cm
3. 
   42 cm
4. 
   80 cm

Q. Circumference of inner and outer circle of a ring are 44 cm and 132 cm respectively, then find the area of the ring.

1. 392 $c{m}^2$
2. 441 $c{m}^2$
3. 576 $c{m}^2$
4. 1232 $c{m}^2$

Q.

Area of a circular field is 3850 $c{m}^2$. What is the perimeter of that field? ( Take $\pi =\frac{22}{7}$)

1. 385 cm²

2. 192.5 cm²

3. 150 cm²

4. 220 cm²

Q.

Figure depicts a racing track whose left and right ends are semi-circular. The distance between the two inner parallel line segments is 60 m and they are each 106 m long. If the track is 10 m wide, find the distance around the track around the inner edge.

1. 301

2. 400

3. 310

4. 320

Q. A wire is bent into the form of a square of side 27.5 cm. The wire is straightened and bent into the form of a circle. What will be the radius of the circle so formed?
[3 marks]

Q. Question 1
Find the radius of a circle whose circumference is equal to the sum of the circumference of two circles of radii 15 cm and 18 cm.

Q.

Find the circumference of the circle given in the figure below.
(Take $\pi$ as $\frac{22}{7}$)

1. 120 cm

2. 88 cm

3. 132 cm

4. 8 cm

Q.

Find the length of the third side and the area of a triangle inscribed in a circle of radius 4 cm with one of its side equal to the length of diameter, another side, as well as height equal to the radius of the circle.

1. $8\sqrt{2}cm$, $16\sqrt{2}c{m}^2$

2. $4\sqrt{3}cm$, $16c{m}^2$

3. $4\sqrt{2}cm$, $16\sqrt{2}c{m}^2$

4. $9\sqrt{3}cm$, $16\sqrt{3}c{m}^2$

Q.

In a cycle race, a boy was cycling in such a way that the wheels are making 200 revolutions per minute. Diameter of the wheel is 50cm, what is the cycling speed per hr?

1. 14.7 km/hr

2. 17 km/hr

3. 20 km/hr

4. 18.84 km/hr

Q. If the diameter of a semicircular protractor is $14cm$ then find its perimeter.

1. $76cm$
2. $36cm$
3. $112cm$
4. $162cm$

Q.

If the circumference of a circle is 528 cm, then its area is ______ $c{m}^2$.

$(\pi =\frac{22}{7})$

1. 22176

2. 22576

3. 23176

4. 24576

Q. Find the perimeter of a semicircle whose diameter is 14 cm.

1. 21 cm
2. 22 cm
3. 36 cm
4. 44 cm