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an arc of a circle subtends an angle 60 at the centre of the circle. find the length of the arc if the radius of the circle is 42 cm. (π= 22 7 ) ( = 22 7 ) .

User Kitchi
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Final answer:

To find the arc length of a circle that subtends a 60° angle with a radius of 42 cm, the formula (Central Angle / 360°) × Circumference is used. The circumference is first calculated using C = 2πr, yielding a length of 504 cm, from which the arc length is derived to be 84 cm.

Step-by-step explanation:

To calculate the length of the arc that subtends an angle of 60° at the center of the circle with a radius of 42 cm, we shall use the formula relating the arc length, radius, and central angle in degrees. The circumference C of a circle is given by C = 2πr, and the arc length formula for a circle is:

Arc length (As) = (Central Angle / 360°) × Circumference of the Circle

Here, our central angle (Θ) is 60°, and the radius (r) is 42 cm. Using the provided value of π as 22/7, the circumference of the circle is C = 2 × (22/7) × 42 cm.

We can calculate the circumference of the circle as follows:

C = 2 × (22/7) × 42 = 2 × 6 × 42 = 2 × 252 = 504 cm

Now, we can find the arc length using the formula:

As = (60°/360°) × 504 cm = (1/6) × 504 cm = 84 cm

Therefore, the arc length is 84 cm.

User Loreny
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