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imationrouter03
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A coil is to be used as an immersion heater for boiling water. The coil is to operate at a voltage of 130 V and is to heat an amount of water with a volume of 251 cm^3 by 80.0 degree celsius in a time interval of 6.30 minutes.
Use 4190 J/(kg*K) for the specific heat capacity of water and 1000 kg/m^3 for the density of water.
The question is :
What must the resistance of the coil be (assumed temperature-independent)?
I have tried the following:
i solved for the m=DV=(1000kg/m^3)(2.51*10^-6m^3)=.251 kg
then i solved for Q=mcdeltaT
deltaT=80C+273=353K
Q=.251 kg(4190J/(kg*K))(353K)=371246.57J
then i divided it by 6.30 min
Q=(371246.57J/6.30min)*(1min/60s)=982.13J/s
R=V^2/P=(130^2)/(982.13)=17.207ohms
This sadly didn't work...please help me on this level 2 problem
Use 4190 J/(kg*K) for the specific heat capacity of water and 1000 kg/m^3 for the density of water.
The question is :
What must the resistance of the coil be (assumed temperature-independent)?
I have tried the following:
i solved for the m=DV=(1000kg/m^3)(2.51*10^-6m^3)=.251 kg
then i solved for Q=mcdeltaT
deltaT=80C+273=353K
Q=.251 kg(4190J/(kg*K))(353K)=371246.57J
then i divided it by 6.30 min
Q=(371246.57J/6.30min)*(1min/60s)=982.13J/s
R=V^2/P=(130^2)/(982.13)=17.207ohms
This sadly didn't work...please help me on this level 2 problem