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The radii of two circles are 19 cm and 9 cm respectively. Find the radius of the circle
Solution: Circumference of first circle = 2 πr = 2π x 19 = 38π cm Circumference of second circle = 18π cm Or, 2πr = 56π Or, 2r = 56 Or, r = 28 cm Circumference of...
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The radii of two circles are 8 cm and 6 cm respectively. Find the radius of the circle having area equal to the sum of the areas of the two circles.
Answer:Area of first circle = πr2 = π82 = 64π sq cm Area of second circle = π62 = 36π sq cm As per question; area of the largest circle = 64π + 36π = 100π...
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If the perimeter and the area of a circle are numerically equal, then the radius of the circle is
Let radius of the circle =r if perimeter = area 2πr=πr² 2r =r²----(1) if r=2 2*2 =2² 4=4 So, correct option is (A) r = 2 units
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A circle with radius a touching x acis at origin find its origin
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A stone is released from the top of a tower of height 19.6 m. Calculate its final velocity just before touching the ground.
According to the equation of motion under gravity v2 − u2 = 2gs Where, u = Initial velocity of the stone = 0 m/s v = Final velocity of the stone s = Height...
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Write True or False: Give reasons for your answers. (i) Line segment joining the centre to any point on the circle is a radius of the circle.
(i) True (ii) False (iii) False (iv) True (v) False (vi) True
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If the lateral surface of a cylinder is 94.2 cm2 and its height is 5 cm, then find (i) radius of its base (ii) its volume (Use π = 3.14)
Here, h = 5 cm, 2πrh = 94.2 cm2. (i) 2πrh = 94.2 ⇒ 2 × 3.14 × r × 5 = 94.2 ⇒ r = 94. 2/ 2x 3.14x 5 = 3 Hence, base...
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How can you distinguish between a plane mirror, a concave mirror and a convex mirror without touching them?
By observing the virtual images formed by the three mirrors, we can distinguish between the mirrors as: (i) Plane mirror will produce an image of the same size, (ii) Concave mirror will...
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The radius of a circle is stated as 2.12 cm. Its area should be written as
(b) 14.1 cm2 Explanation: Area of a circle, A = πr2 On putting the values, we get: A=22/7×2.12×2.12 ⇒A=14.1 cm2 The rules to determine the number of significant digits says that in the multiplication of two...
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The radius of a circle is stated as 2.12cm. Its area should be written as (a) 14cm^2
(b) 14.1 cm2 Explanation: Area of a circle, A = πr2 On putting the values, we get: A=22/7×2.12×2.12 ⇒A=14.1 cm2 The rules to determine the number of significant digits says that in the multiplication of two...
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