Circumference of a Circle

Q. The diameter of a cart wheel is $2.1m.$ Find the distance traveled when it completes $100$ revolutions.

1. $105\pi$
2. $52.5\pi$
3. $420\pi$
4. $210\pi$

Q.

The diameter of a circle is $18cm$. What is its

1. Radius
2. Circumference

Q.

Diameter of a bike wheel is 80 cm. Number of complete rotations the wheel makes to cover a distance of 176 m is

1. 55

2. 120

3. 80

4. 70

Q. Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, for how long does he walk?

Q. The perimeter of the given figure is:

1. 12.4 cm
2. 11 cm
3. 10.2 cm
4. 11.5 cm

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. 18.84 km/hr

4. 20 km/hr

Q. Find the circumference of a circle of radius 5 cm.

1. $10\pi$ cm
2. $5\pi$ cm
3. $20\pi$ cm
4. $15\pi$ cm

Q. Find the distance covered by the tip of the second hand of a clock in $1$ minute if the hand is $8$ cm long.

1. $16\pi$
2. $32\pi$
3. $16$
4. $32$

Q.

Question 69

The areas of two circles are in the ratio 49 : 64. Find the ratio of their circumferences.

Q.

How do you find diameter from the circumference of a circle?

Q.

Circumference $\mathrm{C}$ of a circle can be found by multiplying diameter $\mathrm{d}$ with ___.

Q. What is the cicumference of a circle of radius $r$ and diameter $d$?

1. $\mathrm{\pi r}$
2. $2\mathrm{\pi r}$
3. $2\mathrm{\pi d}$

Q. Which of the following statements is\are correct for $\pi$?

1. $\pi$ is an irrational number.
2. $\pi$ is ratio of circumference of a circle to diameter of the circle.
3. Value of $\pi$ is 3.1415...
4. $\pi$ is a rational number.

Q. If the circumference of a circle is $40\pi m,$ then its radius is (in $m$)

1. $20$
2. $20\pi$
3. $40$
4. $40\pi$

Q. The diameter of a wheel of a bus is 90 cm which makes 315 revolutions per minute. Determine its speed in kms per hour.

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

Q.

If the circumference of a circle is $66m$ then radius is $:$

1. $21m$

2. $10.5m$

3. $14m$

4. $20m$

Q. The radius of a circle is $5units$. What is the circumference of the circle?

1. $Circumference=5\pi$
2. $Circumference=10\pi$
3. $Circumference=15\pi$
4. $Circumference=20\pi$

Q. The radius of circle is half the side of the equilateral triangle whose perimeter is $48$ cm. What is the length of circumference of circle ? ($\pi =3.14$)

1. $50.24$ cm
2. $25.12$ cm
3. $51$ cm
4. $43$ cm

Q. The figure consists of 4 semicircles and 2 quarter circles.
If OA = OB = OC = OD = 28 cm, find the area of shaded region.

Q. Given that diameter of a circle is $d$ and radius of the circle is $r$. Find circumference of the circle.

1. $\pi \times d$
2. $2\pi \times r$
3. $2\pi \times d$
4. $\pi \times r$

Q. Priyanka took a wire and bent it to form a circle of radius 14 cm. She bent it into a rectangle with one side 24 cm long. What is the length of the wire? Which figure encloses more area, the circle or the rectangle?

Q.

Find the area of the sector whose arc is making an angle of 60∘ at the center of a circle of radius 3.2 cm. What will be the area of the balance sector?

I saw the ans to this ques but did not understand. Can u pls make me understand in a simple way?

Q.

If a circle has a diameter of $\text{4 inches}$, what is the circumference ?

Q. A circular track is made for running exercises whose center is always $70$ m away from the person who is running on the circular track. How many rounds are required for the runner to complete $1.760$ Km running ?$(\pi =\frac{22}{7})$

1. $8\text{round}$
2. $4\text{round}$
3. $3.5\text{round}$
4. $5\text{round}$

Q. What is the perimeter of a circle is also known as?

1. Radius
2. Diameter
3. Circumference
4. Eccentricity

Q.

If r is the radius of a circle such that $\pi r^2$= 2$\pi$r, what is the diameter of the circle?

__

Q. The distance between the center of the circle and the point on the circumference is 14.7 cm. Find the length of circumference of the circle. ($\pi =\frac{22}{7}$).

1. $92.4$ cm
2. $46.2$ cm
3. $86$ cm
4. $82.4$ cm

Q.

When the circumference of a circle is divided by its diameter we get a constant value and it is called as ____

1. Varying

2. Constant

3. Cube

4. None of the above

Q. Is the circumference of the circle equals to $2\pi$ times its diameter?

1. Yes
2. No