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प्रश्न
A cylinder of circumference 8 cm and length 21 cm rolls without sliding for `4 1/2` seconds at the rate of 9 complete rounds per second. Find the distance travelled by the cylinder in `4 1/2` seconds.
उत्तर
Circumference of cylinder = 8 cm
Therefore, radius = `c/(2pi) = (8 xx 7)/(2 xx 22) = 14/11 cm`
Length of the cylinder (h) = 21 cm
If distance covered in one revolution is 8 cm, then distance covered in 9 revolution = 9 × 8 = 72
Therefore, distance covered in `4 1/2` seconds
= `72 xx 9/2 cm`
= 324 cm
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