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PLEASE NEED HELP URGENT
019 (part 1 of 2) 10.0 points
A Carnot engine has a power output of
193 kW. The engine operates between two
reservoirs at 25° C and 575°C.
How much thermal energy is absorbed each
hour?

Answer in units of J.
020 (part 2 of 2) 10.0 points
How much thermal energy is lost per hour?
Answer in units of J.

Respuesta :

Answer:

1.07×10⁹ J

3.76×10⁸ J

Explanation:

The efficiency of a Carnot engine is equal to the work output divided by the heat input. It is also equal to one minus the ratio of the cold temperature to the hot temperature.

[tex]\huge \text {$ \eta=\frac{\.W_{out}}{\.Q_{in}}=1-\frac{T_C}{T_H} $}[/tex]

Part 1 of 2

Plug in values and solve for Q (make sure to use absolute temperatures).

[tex]\Large \text {$ \frac{193\ kW}{\.Q_{in}} =1-\frac{25+273\ K}{573+273\ K} $}\\\Large \text {$ \frac{193\ kW}{\.Q_{in}} =0.649 $}\\\Large \text {$ \.Q_{in} =298\ kW $}\\\Large \text {$ \.Q_{in} =298\frac{kJ}{s}\times\frac{3600\ s}{hr} $}\\\Large \text {$ \.Q_{in} = 1,071,300\frac{kJ}{hr} $}\\\Large \text {$ \.Q_{in} = 1.07\times10^9\frac{J}{hr} $}[/tex]

Part 2 of 2

Energy is conserved, so the heat in must equal the sum of the heat out and the work out.

[tex]\Large \text {$ \.Q_{in}=\.Q_{out}+\.W_{out} $}\\\Large \text {$ 1.07\times10^9\frac{J}{hr} =\.Q_{out}+193,000\frac{J}{s}\times\frac{3600\ s}{hr} $}\\\Large \text {$ \.Q_{out}=3.76\times10^8\frac{J}{hr} $}[/tex]

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