Advertisements
Advertisements
प्रश्न
If the radius of a circle is tripled, the area becomes ______.
पर्याय
9 times
3 times
6 times
30 times
Advertisements
उत्तर
If the radius of a circle is tripled, the area becomes 9 times.
Explanation:
Let r be the radius of a circle.
∴ Area of circle = πr2
If radius is tripled, then new radius will be 3r.
∴ Area of new circle = π(3r)2 = 9π2 = 9 times of original
Hence, the area of a circle becomes 9 times to the original area.
APPEARS IN
संबंधित प्रश्न
Find the perimeter of the adjoining figure, which is a semicircle including its diameter.
The base of an isosceles triangle measures 80 cm and its area is 2 `360 . cm^2` Find the perimeter of the triangle.
In a hospital used water is collected in a cylindrical tank of diameter 2 m and height 5 m. After recycling, this water is used to irrigate a park of hospital whose length is 25 m and breadth is 20 m. If tank is filled completely then what will be the height of standing water used for irrigating the park.
The area of a circle is 220 cm2. The area of ta square inscribed in it is
The area of the sector of a circle of radius 10.5 cm is 69.3 cm2. Find the central angle of the sector.
In the given figure, PSR, RTQ and PAQ are three semicircles of diameter 10 cm, 3 cm and 7 cm respectively. Find the perimeter of shaded region. [Use π= 3.14]
Four equal circles, each of radius 5 cm, touch each other, as shown in the figure. Find the area included between them.
Find the area of the shaded region in the given figure, where a circular arc of radius 6 cm has been drawn with vertex of an equilateral triangle of side 12 cm as centre and a sector of circle of radius 6 cm with centre B is made.
A child draws the figure of an aeroplane as shown. Here, the wings ABCD and FGHI are parallelograms, the tail DEF is an isosceles triangle, the cockpit CKI is a semicircle and CDFI is a square. In the given figure, BP ⊥ CD, HQ ⊥ FI and EL ⊥ DF. If CD = 8 cm, BP = HQ = 4 cm and DE = EF = 5 cm, find the area of the whole figure.
Find the area of a flat circular ring formed by two concentric circles (circles with the same centre) whose radii are 9 cm and 5 cm.
