Question

A body cools from 100 to 90 in 10 minutes and from 90 to 80 in 15 minutes find.the temperature of surrounding is

Answer 1

Let the room temperature of be Ф

The change in temperature of the body from (100 - Ф) to (90 - Ф) is (10 - 2Ф)


Thus the cooling rate is :

(10 - 2Ф) / 10

From (90 - Ф) to (80 - Ф) we have :

(10 - 2Ф) / 15

Equating the two

100 - 20 = 150 - 30Ф

50 = 10Ф

Ф = 5°