Calculate how many Kgs of water flows through the plant

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AI Thread Summary
To calculate the mass of water flowing through the power station, the thermal energy dissipated is crucial, which is 1.5 x 10^8 W. Given that heating 1 kg of water by 3°C requires 12,552 J, the total energy dissipated per second can be used to find the mass of water. By dividing the total thermal energy (1.5 x 10^8 J) by the energy required to heat 1 kg of water (12,552 J), the mass flow rate can be determined. The efficiency of the power station is not necessary for this calculation since the thermal energy provided is already specified. This approach leads to the solution for the kilograms of water flowing through the plant each second.
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Homework Statement


"A power station with an efficiency of 0.4 generates 10^8W of electric power and dissipates 1.5*10^8W of thermal energy to the cooling water that flows through it. Knowing that the specific heat of water in SI units is 4184J/KgºC, calculate how many Kgs of water flows through the plant each second if the water is heated through 3 Celsius degrees"


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The Attempt at a Solution




I have no idea. This is way above me.
Someone please explain this to me!
 
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Let's look at any given second. Then how much energy is put into the water? The specific heat of water is given, so you know that it takes 4184 * 3 = 12552 J to heat one kilogram of water by three degrees, so you should then be able to calculate how many kilograms you can heat with the available energy.
 


I understand so far, but I don't understand the available energy.
Efficiency = T(hot)-T(cold)/T(hot) ...right?

What is the available energy?I tried
(1.5x10^8)-(10^8)/(1.5x10^8)=0.333333

Am I headed in the right direction?
 


They already tell you how much is going to thermal dissipation in the water. The efficiency isn't really needed.

Figure the total number of joules dissipated and thence how many kilograms are needed to do it given the number of joules that 1 kg heated 3° carries.
 
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