Transmission Of Heat Question 185
Question: In a room where the temperature is $ 30^{o}C $ , a body cools from $ 61^{o}C $ to $ 59^{o}C $ in 4 minutes. The time (in min.) taken by the body to cool from $ 51^{0}C $ to $ 49^{0}C $ will be
[UPSEAT 2000]
Options:
A) 4 min
B) 6 min
C) 5 min
D) 8 min
Show Answer
Answer:
Correct Answer: B
Solution:
First case, $ \frac{61-59}{4}=K[ \frac{61+59}{2}-30 ] $ ?..(i) Second case, $ \frac{51-49}{t}=K[ \frac{51+49}{2}-30 ] $ ?..(ii) By solving equation (i) and (ii) we get t = 6 min.
BETA
