Q1:
Assertion : In a circle of radius 6 cm, the angle of a sector 60o. Then the area of the sector is 186/7 cm2.
Reason: Area of the circle with radius r is πr2.
Q2:
Assertion : The length of the minute hand of a clock is 7cm. Then the area swept by the minute hand in 5 minutes is 125/6cm2.
Reason : The length of an arc of a sector of angle θ and radius r is given by l = θ/360 x 2πr
Q3:
Assertion : If the outer and inner diameter of a circular path is 10 m and 6 m then area of the path is 16π m2.
Reason : If R and r be the radius of outer and inner circular path = π(R2 -r2).
Q4:
Assertion : If a wire of length 22 cm is bent in the shape of a circle, then area of the circle so formed is 40 cm2.
Reason : Circumference of the circle = length of the wire.
Q5:
Assertion : If the circumference of two circles are in the ratio 2 : 3 then ratio of their areas is 4 : 9.
Reason : The circumference of a circle of radius r is 2πr and its area is πr2.
Q6:
Assertion (A): The diameter of a circle whose area is equal to the sum of the areas of the two circles of radii 24 cm and 7 cm is 50 cm.
Reason (R): If the perimeter and the area of a circle are numerically equal, then the radius of the circle is 2 units.
Q7:
Assertion (A): In covering a distance s meter, a circular wheel of radius r meter makes s/2πr revolution.
Reason (R): The distance travelled by a circular wheel of diameter d cm in one revolution is 2πd cm.
Q8:
Assertion (A): If circumferences of two circles are equal, then their areas will be equal.
Reason (R): If the areas of two circles are equal, then their circumferences are equal.
Q9:
Assertion : If the circumference of a circle is 176 cm, then its radius is 28 cm.
Reason : Circumference = 2π x radius
Q10:
Assertion: A wire is looped in the form of a circle of radius 28 cm. It is bent into a square. Then the area of the square is 1936 cm2.
Reason : Angle described by a minute hand in 60 minutes = 360o.
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