Question

2L water at 27°C is heated by a 1kw heater in an open container. On an average heat is lost to surrounding at the rate 160J/s.the time required for the temperature to reach 77°C

Answer 1

Answer:

8min 2 sec

Explanation:

given=

water=2l

so,2l=2000kg. specific temperature is 4.2

now;P=1000-160=840

Q=MS(t2-t1)

andQ=pt. through thisT=Q/p______eq1

put the value of Qin eq1

mS(t2-t1)/p=t

2000×4.2 ×(77_27)/840

2000×4.2×50/840

42000/84=500

now;500/60=8.2