Question

Certain quantity of water cools from 70°C in the first 5 min and to 54°C in the next 5 min.the temperature of the surrondings is​

Answer 1

Answer:

According to Newton's law of cooling, rate of cooling is directly proportional to the temperature difference between the body and its surroundings. where θ₀ is the temperature of the surroundings. then θ₁ = 70°C and θ₂ = 60°C and t = 5 minutes. then θ₁ = 60°C and θ₂ = 54°C and t = 5 minutes

Answer 2

Explanation:

Apply Newton's law of cooling

Let the temperature of the surrounding be t°C

For the first case,

( 70 - 60 ) / 5 min = K( 65°C - t°C )

_[65° is average of 70°C and 60°C ]

10 / 5min = K ( 65°C - t °C ) _[i]

For second case, ( 60 - 54 ) / 5min = K ( 57 - t )

_[ii] ... 57° is average of 60°C and 54°C ]

From Eq [i] and [ii]

10/6 = ( 65 - t ) / ( 57 - t )

So, t = 45°C

The temperature of the surrondings is 45°C !