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    1. Find the

    (a) arc length

    (b) area of the sector of circle with centre O.

    (a) ________________________[1]

    225

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    (b) ________________________[1]

    2. The diagram below shows a sector AOB of radius 8 cm and arc length 12 cm.

    Calculate

    (a) AOB in terms of degrees

    (b) the length AB

    (c) the perimeter of the shaded region

    BA

    O

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    (a) ________________________[2]

    (b) ________________________[3]

    (c) ________________________[1]

    3a) Convert 160 to radians, giving your answer to one decimal place. [1]

    3b) The diagram shows a cross section of a drainage pipe of radius 36 cm. The drainage pipe contains some

    water.

    i) Find the area of the triangle ORS. [1]

    ii) Find the area of the segment occupied by the water. [2]

    R S

    O

    110 36cm

    water

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    4. The shaded area in the diagram represents the part of the flat windscreen of a car which is being wiped

    by the windscreen wiperAB.

    The wiper rotates through 150 about O.

    OA = OA = 7 cm andAB =AB= 35 cm.

    (a) Leaving your answer in terms of,

    calculate

    (i) the length of the arc AA, [2]

    (ii) the length of the arcBB, [2]

    (iii) the ratio of the arc lengths AA:BB [1]

    (b) Taking the value of 3.142= ,

    calculate

    (i) the area of the screen which is wiped, [3]

    (ii) the perimeter of the screen which is wiped. [2]

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    5. The diagram below shows a sectorAOB of radius 7 cm. Find

    (a) the length of arcAB, [2]

    (b) the area of sectorAOB, [2]

    (c) the area of triangleAOB, [2]

    (d) the area of the shaded segment. [2]

    0.7 rad

    O

    B

    A7 cm

    7 cm

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    6. The diagram shows the layout of a childrens playground.PQR is a triangle with QR = 22 m and PR = 25

    m.PRSis a sector of a circle, centreR, radius 25 m. QRSis a straight line.

    Calculate(a) Calculate the length ofPQ. [2]

    (b) A slide is fixed at R. The angle of elevation from Q to the top of the slide is

    7.8. Calculate the height of the slide. [3]

    (c) Bushes are planted along the curved boundary,PS, of the playground.Calculate the perimeter of the playground which is surrounded by the bushes. [2]

    P

    Q

    R

    S

    25 m

    22 m

    110

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    The diagram shows a major segment of a circle, centre O, radius 12 cm.A,B andXare

    points on the circumference.AngleAOB = 150, chordAB = 23 cm.

    Calculate(a) the arc length of the major sectorOAXB,

    (b) the perimeter of the major segment.

    Give your answers to both questions in terms of.

    A

    O

    B

    X

    1223

    150

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    Answer (a) cm. [2]

    (b) cm. [1]

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    8. The diagram below is a sectorOPQ, centre O, ando120=POQ .

    (a) Given that the arc length is 2

    12 cm, find the radius.

    (b) Find the sector area, leaving your answer in .

    Answer (a) ___________________________ cm

    (b)__________________________ cm2

    [2]

    [2]

    O

    P

    Q

    120o

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    9

    .

    OXYis a sector of a circle with the centerO and radius 12 cm. AngleXOY=

    1.25 radians. Calculate the area of the shaded segment. [3]

    1.25

    12 cm

    X Y

    O

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    10. In the diagram,POQ is a sector of a circle with centre O and radius 10 cm.

    Given that QR is perpendicular to OPandPR= 4 cm, find

    (i) POQ in radians, [2]

    (ii) the area of the shaded region. [3]

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    11.

    The figure shows part of the circle with centre O and radius 10 cm.

    Given that radPOQ 2.1= , find

    (a) the perimeter of the shaded region, [3]

    (b) the area of the shaded region. [3]

    10 cm

    1.2 rad

    10 cm

    Q

    O

    P

    R

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    12. The diagram shows the sectorOAB of a circle, centre O, and radius 8 cm. It is given thatthe length of arcAB is 10 cm.

    (a) Show that angleAOB is 1.25 radian. [1]

    (b) Find the area of the shaded region.

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    Answer : (b) ________________ cm2 [2]

    13. The diagram below shows a plot of land in the shape of sectorOABCD with centre O,

    radius 3.5m.

    ArcsAB = BC = CD. It is given that 6

    5=AOD andPQ = 0.8448m.

    i) Show that OP = 0.9995m. [3]

    ii) Find the area of the shaded region. [3]

    O

    A

    B C

    DP Q

    6

    5

    0.8448

    m

    3.5m

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    14. The diagram shows a right-angled triangle OPQ. An arc of a circle with

    centre O and radius OPcuts OQ atR. Given POQ = 0.84 radians,

    OP= 6 cm andPQ = 6.7 cm, calculate

    (a) the area of sectorOPR,

    (b) the area of the shaded region,

    (c) the perimeter of the shaded region.

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    Answer: (a) [2]

    (b) [2]

    (c) [2

    15. A,B and Care three points on the circumference of a circle with centre O.

    AB is a diameter of the circle and , angleAOC= x o.

    (a) Giving your reasons, find, in terms of x ,

    (i) angleABC, [2]

    (ii) reflex angle AOC. [2]

    (b) Given that that length of the radius OB is 3.5 cm and obtuse angle BOCis 2.4 radians, calculate

    (i) the area of sectorBOC . [2]

    (ii) the area of triangle BOC . [2]

    .

    x

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    16

    In the diagram,POQ is a sector of a circle with centre O and radius 10 cm. Given that

    QR is perpendicular to OPandPR= 6 cm, find

    (a) ROQ in radians,(b) the area of the shaded region.

    O

    10 cm

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    Answer: (a)....[3]

    (b) ...cm2[3]

    17. The diagram, which shows the sectorAOB of a circle, represents a piece of

    card. The radius of the sector is 21 cm and the angle AOB is 120.

    (a) Calculate

    (i) the length of the arcACB, [2]

    (ii) the area of the sector AOB, [2]

    (iii) the area of the segment ACB. [2]

    (b) The card is used to make a hollow cone by joining the edges OA

    and OB. Calculate

    (i) the radius of the base, [1]

    (ii) the height of the cone. [1]

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    18. In the diagram, OPQ is a sector of a circle, centre O and radius 15 cm. OPis parallel to SR.The length of the arcPQ is 18 cm and Sis the mid-point ofOQ.

    Find(i) POQ in radians, [1]

    (ii) the length ofRT, [2]

    (iii) ROT in radians, [2]

    (iv) the area of the shaded region. [3]

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    19. A circle, centre O, has radius 7 cm.

    Pand Q are points on the circumference such that anglePOQ = 1.4 radians.

    Calculate

    (a) the perimeter of the minor sectorPOQ,

    (b) the area of the major sectorPOQ.

    7 cm

    Q

    P

    O

    1.4 rad

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    Answer: (a)______________cm [2]

    (b)_____________cm2 [2]

    21 The diagram below shows a right-angled triangle OPQ. An arc of a circle with centre O

    and radius OPcuts OQ atR.

    Given that POQ = 0.84 radian, OP= 6 cm andPQ = 6.7 cm, calculate

    (a) the area of sectorOPR, [1]

    (b) the area of the shaded region, [1](c) the perimeter of the shaded region. [2]

    O

    P

    R Q

    6 cm 6.7 cm

    0.84 rad

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    22.

    A,B, CandD are points on a circle with centre 0 and radius 8 cm.

    Given that = 100AOC

    Calculate

    (a) ADC [1]

    (b) ABC [1]

    (c) the length of the chord AC . [2]

    (d) area of OAC [2]

    (e) area of segment ABC . [2]

    D

    C

    AO8 cm

    B

    100 8 cm

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    O

    A B

    12

    3

    2

    or

    miners

    se

    23. The pointsA andB lie on a circle, centre O.

    OA = OB = 12 cm and BOA =3

    2radians.

    Calculate(a) the length of the arcAB,(b) the area of the sector OAB,

    (c) the area of the shaded segment.

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    Answer (a) ........................................... cm [2]

    (b) ......................................... cm2 [2]

    (c) ......................................... cm2 [3]

    24

    .Figure 1 shows a circle, centre O,

    passes through A, B, C and D.

    Given that the radius of the circle is 9 cm

    andDOC = 108o.

    Calculate

    (i) DBC, [1]

    (ii) ABD, [2]

    (iii) area of minor sector DOC, [2]

    (iv) area of the segment DEC. [2]

    B

    C

    Figure 1

    O

    A

    D108o

    E

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    10 cm

    25 The diagram shows the sector of a circle.

    The radius of the circle is 10 cm.

    The angle AOB is 2.51 radians.A

    O

    B

    2.51 rad

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    h10 cm

    r

    O

    (a) Find the length of the arc AB. [2]

    (b) Find the area of the sector AOB. [1]

    (c) OA is joined to OB to make a cone as shown.

    (i) Show that the radius, r, of the cone is 6 cm. [1]

    (ii) Find the height, h, of the cone. [2](iii) Find the volume of the cone. [2]