Advertisements
Advertisements
प्रश्न
The radius of a circle whose circumference is equal to the sum of the circumferences of the two circles of diameters 36 cm and 20 cm is ______.
विकल्प
56 cm
42 cm
28 cm
16 cm
उत्तर
The radius of a circle whose circumference is equal to the sum of the circumferences of the two circles of diameters 36 cm and 20 cm is 28 cm.
Explanation:
Circumference of circle = Sum of circumference of two circles
`[("r"_1 = 36/2 = 18 "cm"),("r"_2 = 20/2 = 10 "cm")]`
⇒ 2πR = 2πr1 + 2πr2
2πR = 2π(r1 + r2)
⇒ R = r1 + r2 = 18 + 10
⇒ R = 28 cm.
APPEARS IN
संबंधित प्रश्न
A pendulum swings through an angle of 30º and describes an arc 8.8 cm in length. Find the length of the pendulum.
The perimeter of a sector of a circle of radius 5.2 cm is 16.4 cm. Find the area of the sector.
The side of a square is 10 cm. find the area of circumscribed and inscribed circles.
The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is 210°, find the area of the sector in case.
A square ABCD is inscribed in a circle of radius r. Find the area of the square.
The perimeter of a circular field is 242 m. The area of the field is
The circumference of a circle is equal to the sum of the circumference of two circles having diameters 36 cm and 20 cm. The radius of the new circle is
The perimeter of a sector of a circle of radius 5.6 cm is 27.2 cm. Find the area of the sector.
Construct the circumcircle of the ABC when BC = 6 cm, B = 55° and C = 70°.
The moon is about 384000 km from earth and its path around the earth is nearly circular. Find the length of path described by moon in one complete revolution. (Take π = 3.14)
