Area of a Sector

Q.

An umbrella has 8 ribs which are equally spaced. Assuming the umbrella to be a flat circle of radius 45 cm, find the area in $c{m}^2$ between the two consecutive ribs of the umbrella.

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Q.

A car is provided with 2 non overlapping wipers. The structure of each wiper is as shown in the figure. The brown blade actually wipes the glass sweeping through an angle of ${120}^{\circ }$. If the length of the wiper is 35 cm and length of the blade is 28 cm, find the total area(in $c{m}^2$) cleaned for each sweep.

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Q.

How would you go about finding the area of the major sector?

1. Area of circle - Area of minor sector

2. Area of circle + Area of minor sector

3. Perimeter of the minor sector x radius

4. Perimeter of major sector x perimeter of minor sector

Q. Tick the correct answer in the following:
Area of a sector of angle p (in degrees) of a circle with radius R is

1. 
2. 
3. 
4. 

Q.

Find the area of the shaded region (in $c{m}^2$) as shown in figure of the two concentric circles with centre O and radius 7 $cm$ and 14 $cm$ respectively. Given $\angle$AOC = ${40}^{\circ }$.
(use $\pi$ = $\frac{22}{7}$)

1. 42.1 $c{m}^2$

2. 51.32 $c{m}^2$

3. 67.8 $c{m}^2$

4. 96.5 $c{m}^2$

Q.

The figure consists of 3 semicircles and an equilateral triangle of side 7 cm. Find the area of the entire figure.

1. 78.94 cm²

2. 252.19 cm²

3. 134.75 cm²

4. 253.25 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 area of the track (in $m^2$).

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Q.

Find the area of the shaded region where ABC is a quadrant of radius 5 cm and a semicircle is drawn with BC as diameter.

1. 12.5 $c{m}^2$

2. 7.14 $c{m}^2$

3. 19.64 $c{m}^2$

4. 8.8 $c{m}^2$

Q.

Find the area of the sector in a clock swept by the minute hand in five minutes if the radius is 14 cm.

$\left(Take\pi as\frac{22}{7}\right)$

1. $616c{m}^2$

2. $51.33c{m}^2$
3. $42c{m}^2$
4. None of the above

Q.

In the figure, two small circles touch each other externally at the centre of a bigger circle and these small circles are touched internally by a bigger circle with radius 4 $cm$. Find the area of the shaded region in $c{m}^2$.

1. 27

2. 30

3. 22

4. 35