Question

Certain quantity of water cools form 70°C to 60°C in the first 5 mint and 54°C in the next 5
min. Then what well be the temperature of the surrounding (Ans. 45°C).​

Answer 1

Answer:

45⁰ C

Explanation:

HEY!! HERE IS YOUR REQUIRED ANSWER STEPWISE-:

• Note: water cools from 70 to 60 C in 5 minutes we can apply newtons law of cooling here,
• Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature (i.e. the temperature of its surroundings).
• Let us summarize the information briefly and define notation for this problem.

☆Solution:☆

$\bold{\frac{60 - 70}{5} = -K (65 - T)</p><p>}$

$\bold{ \frac{54 - 60}{5}-K (57 - T)}$

$\bold{ \frac{ - 10}{ - 6} = \frac{65 - T}{57 - T}}$

$\bold{285 - 5T = 195 - 3T}$

$\bold{90 = 2T}$

$\bold{T = 45⁰}$