Question

A bucket full of hot water is kept in a room and it cools from 75°C to 70°C in T₁ minutes, from 70°C to 65°C in T₂ minutes and from 65°C to 60°C in T₃ minutes. Then(a) T₁ = T₂ = T₃ (b) T₁ < T₂ < T₃(c) T₁ > T₂ > T₃(d) T₁ < T₂ > T₃

Answer 1

Answer

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T1-T2/time = k ( T1+T2/2 - T(surronding)) now put the values of temp and time.

Keep time and tsurr as it is in the form of variable only we have 3 different time so we get 3

eq. .5/t1 = k (135/2- Tsu) ,5/t2 = k (125/2-Tsu), .5/t3 =k (115/2 -Tsu) divide two eq at a time the you get a idea about t1, t2 and t3 so you get option b ...

T₁ < T₂ <