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Asked by jain.pradeep | 26th May, 2019, 06:42: PM

Expert Answer:

The curve shows it is almost reaching the surrounding temperature 20 °C and change in temperature keep on decreasing and it is very less at   4  hour.  Hence, temperature will be very near to 20 °C
 
Energy loss  ΔE for change in temperature ΔT is given by  ΔE = m×Cp×ΔT ,  
where m is mass of water and Cp is specific heat of water

if  ΔT = 1°C   ,  then Energy loss per °C,    m×Cp = 8×105 J /°C .................(1)
 
Rate of change of energy loss with repect to time,  (ΔE/Δt) = m×Cp×( ΔT/Δt) = 16×106 J/hour  ................(2)
 
from eqn.(1) and (2),  Rate of temperature falling,  ( ΔT/Δt) = 16×106 / ( 8×105)  = 20 °C/hour
 

Answered by Shiwani Sawant | 28th May, 2019, 02:26: PM

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