SOLUTION: 1
a sector of circle radius 7cm subtending an angle of 270° at the center of the circle,is used to form cone.
a:find the base radius of the cone.
b:calculate the area of the ba
Algebra.Com
Question 1027471: 1
a sector of circle radius 7cm subtending an angle of 270° at the center of the circle,is used to form cone.
a:find the base radius of the cone.
b:calculate the area of the base of the cone correct to the nearest square centimetres. ( take π=22/7).
Answer by Cromlix(4381) (Show Source): You can put this solution on YOUR website!
Hi there,
Angle/360 = Length of arc/Pi x diameter.
270/360 = Length of arc/Pi x 14
Length of arc = (270 x Pi x 14)/360
Length of arc = 32.99cm.(2 decimal places)
When the sector is folded into a cone
the arc length becomes the cone's
circumference.
Circumference = Pi x diameter.
32.99 = Pi x diameter.
Diameter = 32.99/Pi
Diameter = 10.5cm
Diameter = 2 x radius
Radius = Diameter/2
Radius = 10.5/2
Radius = 5.25cm
b) Area of base of cone = Pi x radius^2
Area = Pi x 5.25^2
Area = 86.59cm^2
Area = 87cm^2 (nearest whole square centimetre)
Hope this helps :-)
RELATED QUESTIONS
A sector of a circle 7cm subtending an angle 210 at the centre of the circle, is used to... (answered by josgarithmetic,KMST)
A cone of base radius 7cm was made from a sector of a circle which subtends an angle of... (answered by mananth)
A sector of a cycle of radius 9cm subtending an angle 240 at the centre of the cycle , is (answered by Solver92311,greenestamps)
A sector with an angle 110 degrees at the center of a circle is cut away from a circular... (answered by mananth)
a circle a diameter 28 cm with a sector subtending an angle of 75 at the centre. Find... (answered by mananth,MathTherapy)
A sector of circle has a radius 4cm. It is folded over to form a circular cone. Find the... (answered by ankor@dixie-net.com)
A sector of a circle of radius 8cm subtends an angle 90 degrees at the centre of the... (answered by stanbon)
The area of a sector of a circle with the radius 7cm is 15 square cm. Find the measure of (answered by Theo)
Find the arc length of the subtending arc for an angle of radians on a circle of radius... (answered by Fombitz)