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ALso, please If a wheel with a radius of 30 inches spins at a rate of 500 revolutions per minute, find the approximate linear velocity in miles per hour.
Find the arc length of a circle if the central angle measures 90degrees and the radius measures 30 inches?
回答 (1)
2016-07-18 7:10 am
Arc length
= (2 × π × 30) × (90/360) in
= 15π in
≈ 15 × 3.1416 in
= 47.11 in (to 4 sig.fig.)
Linear velocity
= [500 × (2 × π × 30) / (5280 × 12)] / (1/60) miles/hour
≈ [500 × (2 × 3.1416 × 30) / (5280 × 12)] / (1/60) miles/hour
= 89.25 miles/hour (to 4 sig. fig.)
= (2 × π × 30) × (90/360) in
= 15π in
≈ 15 × 3.1416 in
= 47.11 in (to 4 sig.fig.)
Linear velocity
= [500 × (2 × π × 30) / (5280 × 12)] / (1/60) miles/hour
≈ [500 × (2 × 3.1416 × 30) / (5280 × 12)] / (1/60) miles/hour
= 89.25 miles/hour (to 4 sig. fig.)
收錄日期: 2021-04-18 15:19:51
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