The temperature of a body in air falls from 40 to 24 in 4 minutes. The temperature of the air is 16 . The temperature of the body in the next 4 minutes will be :
- 283
- 563
- 423
- 143
Answer
(2) 563
Solution
Newton's law of cooling: T1-T2t=K ( T1+T22-Ts )
First 4 min: 40-244=K (32-16 ) K= 14 min-1
Next 4 min: 24-T= 24+T2-16
48-2T=24+T-32
T= 563 C
Answer: (2)