Advertisements
Advertisements
प्रश्न
If the numerical value of the area of a circle is equal to the numerical value of its circumference , find its radius.
उत्तर
Given that area of the circle = circumference
\[\pi r^2 = 2\pi r\]
\[ \Rightarrow \pi r^2 - 2\pi r = 0\]
\[ \Rightarrow \pi r\left( r - 2 \right) = 0\]
\[ \Rightarrow r = 0 or r = 2\]
Since radius cannot be equal to 0 so, r = 2
APPEARS IN
संबंधित प्रश्न
The length and breadth of a rectangular garden are in the ratio 9:5. A path 3.5 m wide, running all around inside it has an area of `1911m^2` . Find the dimensions of the garden.
Find the area of the quadrilateral ABCD in which in AB=42 cm, BC=21 cm, CD=29cm, DA=34 cm and diagonal BD = 20 cm.
The adjacent sides of a parallelogram are 32 cm and 24 cm. If the distance between the longer sides is 17.4 cm, find the distance between the shorter sides.
In the following figure, ABCD is a trapezium of area 24.5 cm2 , If AD || BC, ∠DAB = 90°, AD = 10 cm, BC = 4 cm and ABE is quadrant of a circle, then find the area of the shaded region. [CBSE 2014]
How many revolutions a circular wheel of radius r metres makes in covering a distance of s metres?
If the perimeter of a semi-circular protractor is 36 cm, then its diameter is
The minute hand of a clock is 12 cm long. Find the area swept by in it 35 minutes.
The minute hand of a clock is 8 cm long. Find the area swept by the minute hand between 8.30 a.m. and 9.05 a.m.
The following figure shows a square cardboard ABCD of side 28 cm. Four identical circles of the largest possible sizes are cut from this card as shown below.
Find the area of the remaining card-board.
A circular park is surrounded by a road 21 m wide. If the radius of the park is 105 m, find the area of the road.