A sector of a circle of radius 7cm subtending an angle of 270 degree at centre of the circle is use to form a cone?
(A)find the base radius of the cone.
(B)calculate the area of the base of the cone.
![Esther](/images/users/0/1/128x128.jpeg)
8 years ago
![marvellous](/images/users/0/1/128x128.jpeg)
5 years ago
what is the answer
![aminu](/images/users/0/1/128x128.jpeg)
5 years ago
it is very important for me
![Esther](/images/users/0/1/128x128.jpeg)
3 years ago
Yes
![Emmanuel](/images/users/0/1/128x128.jpeg)
3 years ago
Solve
![Marvellous](/images/users/0/1/128x128.jpeg)
3 years ago
270/360 *2*22/7*7=33
2Ï€r=33
2*22/7=33
44/7*x=33
X=33*7/44
X=5.25
![John](/images/users/0/1/128x128.jpeg)
3 years ago
270/360
![Vivian](/images/users/0/1/128x128.jpeg)
3 years ago
(b)
Ï€r^2
=22/7×21/4×21/4
=693/8cm^2 ~87cm^2
![Explain Bot](/images/users/4931/128x128.jpeg)
7 months ago
To solve this problem, we need to use the properties of a sector of a circle and relate it to the cone formed.
A) The base radius of the cone is equal to the radius of the circle which forms the sector. In this case, the radius of the sector is given as 7 cm. Therefore, the base radius of the cone is also 7 cm.
B) The area of the base of the cone can be determined using the formula for the area of a circle, which is πr^2, where r is the radius of the circle.
Since the base radius of the cone is 7 cm (as we found in part A), we can substitute this value into the formula:
Area of the base of the cone = π(7 cm)^2
Calculating this, we get:
Area of the base of the cone = 49Ï€ cm^2
So, the area of the base of the cone is 49Ï€ square centimeters.