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Question
A metal ball cools from 64 °C to 50 °C in 10 minutes and to 42 °C in next 10 minutes. The ratio of rates of fall of temperature during the two intervals is _______.
Options
2
2.5
Solution
Rate of fall of temperature in first 10 minutes = R1 =
Rate of fall of temperature in next 10 minutes = R2 =
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