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1. ### A sector of a circle has a central angle of 90degrees.If the radius is 8inches,then what's the exact area ?

...1. 90 degrees is exactly a quarter of a whole circle . 2. The area of a circle with a radius of 8 inches is Area = πR² = π * ...

2 Answers · Science & Mathematics · 30/09/2009

2. ### Physics question: Rotating Disk (Hint: Use area of a sector of a circle )?

http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electromagnetic%20induction/text/Rotating_disc_and_generators/index.html

1 Answers · Science & Mathematics · 23/03/2015

3. ### what is the radius of the circle ?

60 degrees is 1/6 of 360 degrees (i.e. the whole circle .) Area of sector = 4.72 cm^2 Area of circle = 4.72cm^2 * 6 = 28.32 Area of circle ...

2 Answers · Science & Mathematics · 04/08/2009

4. ### A kite is in the form of a sector of a circle of radius 12cm. if the perimeter of the kite is 38cm, calculate ?

...24 cm Length of the arc = 38 cm - 24 cm = 14 cm Let angle of the sector = theta theta = length of arc/radius theta = 14/12 rad theta = 7/6 rad If angle is 2*PI rad, then area = Pi * r^2 (where r = radius) Angle = 7/6 rad. Therefore...

2 Answers · Science & Mathematics · 20/07/2009

5. ### A sector of a circle has a perimeter 7cm and an area 3cm^2. Find all possible radii?

...radius be r and the angle subtended by the sector at the centre of the circle be a in radian measure a = 7/r The area of the sector is (r^2)* a /2 = 3, so a = 6/r^2 The perimeter of the sector ...

1 Answers · Science & Mathematics · 06/09/2011

6. ### What is the area of a sector with measure of arc equal to 90° and radius equal to 1 foot?

... a measure of arc equal to 360 degrees we can see that the this sector is 90/360=1/4 the area of a circle with radius r as described by the above equation. Thus, the area of ...

3 Answers · Science & Mathematics · 29/11/2012

7. ### in a circle of radius 10cm a sector has an area of 40pi. sq. cm. find degree measure of the arc of the sector ?

...radius of 10 then its area is found by A = πr². A = π(10)² = 100π, so this is the area of the entire circle . Since the area of the sector is only 40π, that is 40π/100π or 40% of the circle . 40% of the circle ...

4 Answers · Science & Mathematics · 28/09/2007

8. ### if a circle has a radius of r. if the arc of a sector measures 3pi/5, what is the area of the sector ?

0.3pi*r^2. Think about it. If the arc measures 1 circle = 2pi, the area = pi*r^2. If it measures 3/5*pi, that's 0.3 of a circle and area = 0.3pi*r*2.

3 Answers · Science & Mathematics · 09/05/2010

9. ### Find the area of a sector with measure of arc equal to 90 degrees and radius equal to 1 foot?

...answer is right for wrong reason. If r not = 1 that formula doesn't work. Area of circle = pi*r^2 Area of quarter circle = pi*r^2/4 = 0.785 ft^2 When r...

2 Answers · Science & Mathematics · 28/09/2007

10. ### physics motion question.?

A = (1/2)r^2.w where w is the sector angle in radians. dA/dt = rw.dr/dt = 6 x 0.42.pi x 0.3 = 2.38 cm^2/s

2 Answers · Science & Mathematics · 27/02/2010