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A vessel contains water at 100^(@)C. The...

A vessel contains water at `100^(@)C`. The temperature falls to `80^(@)` C in time `T_(1)` , and to `60^(@)C` in further time `T_(2)`, then

A

`T_(1) = T_(2)`

B

`T_(1) lt T_(2)`

C

`T_(1) gt T_(2)`

D

`T_(1)^(2) = T_(2)^(3)`

Text Solution

Verified by Experts

The correct Answer is:
B
According to Newton.s law of cooling
`ms((theta_(2)-theta_(1)))/(t) =K ((theta_(2)+theta_(1))/(2)- theta_(0))`
`(T_(1))/(T_(2))=(((80+60)/(2)-theta_(0)))/(((100+80)/(0)- theta_(0)))= (70-theta_(0))/(90- theta_(0))lt 1 `
`:. T_(1) lt T_(2)`
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