Home
Class 10
MATHS
In the given figure, two concentric circ...

In the given figure, two concentric circles with centre O have radii 21 cm and 42 cm. If `/_AOB=60^(@)` find the area of the shaded region.

Text Solution

Verified by Experts

`ar("region" ACDB)=ar("sector"AOB)-ar("sector"COD)`
`={(22/7xx42xx42xx60/360)-(22/7xx21xx21xx60/360)}cm^(2)`
`=(924-231)cm^(2)=693cm^(2)` ltbgt ar(circular ring) `={(22/7xx42xx42)-(22/7xx21xx21)}cm^(2)`
`=(5544-1386)cm^(2)=4158cm^(2)`
Required area `=` ar(circular ring) `-` ar(region ACDB)
`=(4158-693)cm^(2)=3465cm^(2)`
Hence the area of the shade region is `3465cm^(2)`.
Promotional Banner

Similar Questions

Explore conceptually related problems

In the given figure, two concentric circles with centre O, have radii 21 cm and 42 cm. If angleAOB = 60^(@) , Find the ara of the shaded region

In Fig., two concentric circles with centre O, have radi 21cm and 42cm. If angleAOB= 60^@, find 22 the area of the shaded region. ["Use "pi=(22)/(7)]

In the figure, the radii of two concentric circles with centre O are 7 cm and 14 cm and angle AOC = 60^(@) . Find the area of the shaded region.

A B and CD are respectively arcs of two concentric circles of radii 21cm and 7cm and centre O. If /_AOB=30o, find the area of the shaded region.

AB and CD are respectively arcs of two concentric circles of radii 21cm and 7cm and centre O (see Fig.12.32). If /_AOB=30^(@) find the area of the shaded region.

In the given figure PQ and AB are respectively the arcs of two concentric cicles of radii 7 cm and 3.5 cm with centre O. If /_POQ=30^(@) , find the area of the shaded region.

In the given figure two concentric circles with centre O are of radii 5 cm and 3 cm. From an external point P, tangents PA and PB are drawn to these circles. If AP =12 cm find BP.

AB and CD are respectively arcs of two concentric circles of radii 21 cm and 7 cm and centre O (See figwe). If AOB = 30°, find the area of the shaded region.

In the give figure, the sectors of two concentric circles of radii 7 cm and 3.5 cm are shown. Find the area of the shaded region.