The area of $\odot( O , r)$ is $240\,cm ^{2} .$ In $\odot( O , r),$ minor $\widehat{ ACB }$ subtends an angle of measure $45$ at the centre. Then, the area of minor sector $OACB$ is $\ldots \ldots \ldots . . cm ^{2}$.
The area of $\odot( O , r)$ is $240\,cm ^{2} .$ In $\odot( O , r),$ minor $\widehat{ ACB }$ subtends an angle of measure $45$ at the centre. Then, the area of minor sector $OACB$ is $\ldots \ldots \ldots . . cm ^{2}$.
- A
$30$
- B
$40$
- C
$60$
- D
$80$
Similar Questions
Which of the following correctly matches the information given in Part $I$ and Part $II$ ?
Part $I$
Part $II$
$1.$ Formula to find the length of a minor arc
$a.$ $C=2\pi r$
$2.$ Formula to find the area of a minor sector
$b.$ $A =\pi r^{2}$
$3.$ Formula to find the area of a circle
$c.$ $l=\frac{\pi r \theta}{180}$
$4.$ Formula to find the circumference of a circle
$d.$ $A=\frac{\pi r^{2} \theta}{360}$
Which of the following correctly matches the information given in Part $I$ and Part $II$ ?
| Part $I$ | Part $II$ |
| $1.$ Formula to find the length of a minor arc | $a.$ $C=2\pi r$ |
| $2.$ Formula to find the area of a minor sector | $b.$ $A =\pi r^{2}$ |
| $3.$ Formula to find the area of a circle | $c.$ $l=\frac{\pi r \theta}{180}$ |
| $4.$ Formula to find the circumference of a circle | $d.$ $A=\frac{\pi r^{2} \theta}{360}$ |
The circumference of a circular ground is $352\, m$. Find the area of the ground. (in $m^2$)
The circumference of a circular ground is $352\, m$. Find the area of the ground. (in $m^2$)
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 (in $cm$)
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If the sum of the areas of two circles with radii $R_{1}$ and $R_{2}$ is equal to the area of a circle of radius $R$, then
If the sum of the areas of two circles with radii $R_{1}$ and $R_{2}$ is equal to the area of a circle of radius $R$, then
The radius of a wheel of a car is $21 \,cm$. If it makes $800$ rotations per minute, find the speed of the car in $km / h$.
The radius of a wheel of a car is $21 \,cm$. If it makes $800$ rotations per minute, find the speed of the car in $km / h$.