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(B) Solve the following subquestions:
(i) For an arc ABC, 0-90° radius-7 cm. Find its length.

User Adkane
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Final answer:

To find the length of an arc with a central angle of 90° and a radius of 7 cm, use the arc length formula s = (θ/360) × 2πr, which yields an approximate length of 11 cm for θ = 90°.

Step-by-step explanation:

To solve for the length of an arc ABC with a central angle of 0-90° and a radius of 7 cm, we can use the formula for arc length, which is a fraction of the circumference of the entire circle. The formula is:

arc length (s) = (θ/360) × 2πr

where θ is the angle in degrees and r is the radius of the circle. For this example:

• θ is within 0-90° (let's assume θ is 90° for calculation purposes).

• r is 7 cm.

Therefore, the arc length s would be:

s = (90/360) × 2π × 7

s = (1/4) × 2π × 7

s = ½π × 7

s = 3.5π cm

Since π is approximately 3.1416, the approximate arc length s is:

s = 3.5 × 3.1416

s ≈ 11 cm

This is the arc length for an arc of 90 degrees and a radius of 7 cm.

User Himanshu Mohta
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