First Law of Thermodynamics: Conservation of Energy

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According to the First Law of Thermodynamics, what is the relationship between the net heat supplied to a system and the net work done by the system?

There is no relationship between the net heat supplied and the net work done.

The net heat supplied to the system is less than the net work done by the system.

The net heat supplied to the system is equal to the net work done by the system. (correct)

The net heat supplied to the system is greater than the net work done by the system.

What was the historical view of heat before Joule's experiments in the 1840s?

Heat was not well understood before Joule's experiments.

Heat was considered to be a form of energy.

Heat was considered to be a fluid known as 'caloric'. (correct)

Heat was considered to be unrelated to work.

In the steam plant problem, what is the relationship between the specific heat supplied to the steam in the boiler ($q_{in}$) and the specific heat rejected by the system in the condenser ($q_{out}$)?

$q_{in} = q_{out}$

There is no relationship between $q_{in}$ and $q_{out}$.

$q_{in} < q_{out}$

$q_{in} > q_{out}$ (correct)

What is the purpose of the feed pump in the steam plant problem?

To pump the condensate water back into the boiler. Signup and view all the answers

What is the unit for the steam flow rate $m$ calculated in the steam plant problem?

kg/s Signup and view all the answers

What is the significance of the system boundary shown in the diagram of the steam plant?

It defines the region where the First Law of Thermodynamics is applied. Signup and view all the answers

What is the equation used to apply the first law of thermodynamics in this problem?

ΣdQ = ΣdW Signup and view all the answers

What is the net heat flow (Σdq) in the cycle according to the text?

700 kJ/kg Signup and view all the answers

What does the non-flow equation state about a system undergoing a cycle?

Net heat supplied equals net work output for a complete cycle Signup and view all the answers

What does it indicate about the system if the final intrinsic energy is higher than the initial value?

Difference between net heat and net work increased system's intrinsic energy Signup and view all the answers

What is the steam mass flow rate in kg/s according to the calculations provided?

1.421 kg/s Signup and view all the answers

Which equation is used to relate the steam mass flow rate to the net work output in the problem?

mṁ(700) = 995 Signup and view all the answers

What is the First Law of Thermodynamics a statement of?

The principle of conservation of energy Signup and view all the answers

If a system undergoes a complete thermodynamic cycle and net work is done by the system, where does the mechanical energy come from?

It comes from the heat supplied to the system Signup and view all the answers

If a system undergoes a complete thermodynamic cycle and net work is done on the system, what is true about the heat and work involved?

The net work done on the system is equal to the net heat supplied Signup and view all the answers

If a system undergoes a complete thermodynamic cycle and returns to its initial state, what can be said about its intrinsic energy?

It must be unchanged Signup and view all the answers

In a thermodynamic cycle, if the net work done by the system is positive, what can be said about the net heat supplied to the system?

It must be positive Signup and view all the answers

According to the First Law of Thermodynamics, which of the following statements is true?

Energy can be neither created nor destroyed Signup and view all the answers

First Law of Thermodynamics: Conservation of Energy

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