Question
A cylindrical roller of diameter 1.6 metres and length 2.4
metres makes 15 revolutions per minute. What area can it cover in 10 minutes?Solution
ATQ,
CSA = 2 × π × radius × height
= 2 × (22/7) × (1.6/2) × 2.4
= 2 × (22/7) × 0.8 × 2.4 = (84.48/7) m²
Area in 1 minute = 15 × (84.48/7) = 1,267.2/7 m²
Area in 10 minutes = 10 × (1,267.2/7) = 12,672/7 = 1,810.29 m²
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