Question

A tub of hot water cools from 80°C to 75°C in time t₁ from 75°C to 70°C in time t₂, and from 70°C to 65°C in time t₃ then:

पर्याय

• t₁ > t₂ > t₃

• t₃ > t₂ > t₁

• t₂ > t₁ > t₃

• t₁ > t₂ > t₄

Answer 1

t₃ > t₂ > t₁

Explanation:

According to Newton's law of cooling.

Rate of cooling ∝ Mean temperature difference

`(Δ"T")/"t" ∝ (("T"_1 + "T"_2)/2 - "T"_0)`

`"t" ∝ 1/((("T"_1  +  "T"_2)/2 - "T"_0))`

So, t₃ > t₂ > t₁