# Recent questions in First law of Thermodynamics

Recent questions in First law of Thermodynamics
Mariah Sparks 2022-07-23

### Why is small work done always taken as $dW=F\cdot dx$ and not $dW=x\cdot dF$ ?

Aphroditeoq 2022-07-22

### When an isolated ideal gas gets (adiabatically) compressed due to its own gravity, its gravitational potential energy increases. Does this mean its kinetic energy will reduce (due to conservation of total energy) and the gas will cool down? Does it not violate first law of thermodynamics which says an ideal gas should heat up on compression?

Emmanuel Pace 2022-07-22

### So I was doing problem and used formula Eq.1 to find Energy in isochoric process.$\mathrm{\Delta }E=\frac{3}{2}pV$and get a bad result so now i saw the correct formula:$\mathrm{\Delta }E=n{c}_{v}\mathrm{\Delta }T$What is doing on? can somebody link consistent source of that formulas etc.?

agantisbz 2022-07-22

### Consider the following reaction in the vessel with a movable piston.$X\left(g\right)+Y\left(g\right)\to Z\left(s\right)$For this reaction, , the piston moves up, and the system absorbs 388 J of heat from its surroundings.(a) Does the system do work? (b) How much work?

Nash Frank 2022-07-22

### Change in state {for example from liquid to gas} is an isothermal process but the change in internal energy is not zero in this process isn't this contradictory?

Taniya Burns 2022-07-22

### Deriving $P{V}^{n}=\text{constant}$ for polytropic processes?

Almintas2l 2022-07-20

### Is enthalpy also valid for liquids and solids?

Luciano Webster 2022-07-19

### What is the First Law of Thermodynamics? Give 1 situation wherein the first law can be applied and explain how it is applied.

Markus Petty 2022-07-18

### The first law of thermodynamics$\text{d}Q=\text{d}U+p\text{d}V-\mu \text{d}N$is equivalent to saying: Q is a differentiable real valued function of U,V and N, so that we can write $\text{d}Q=\frac{\mathrm{\partial }Q}{\mathrm{\partial }U}\text{d}U+\frac{\mathrm{\partial }Q}{\mathrm{\partial }V}\text{d}V+\frac{\mathrm{\partial }Q}{\mathrm{\partial }N}\text{d}N$, and $\frac{\mathrm{\partial }Q}{\mathrm{\partial }U}=1$. Also, we define $p=\frac{\mathrm{\partial }Q}{\mathrm{\partial }V}$ and $-\mu =\frac{\mathrm{\partial }Q}{\mathrm{\partial }N}$Is that it?

agantisbz 2022-07-18

### Bernoulli's principle is an example of which law of thermodynamics. Explain why?

Bernard Boyer 2022-07-17

### Suppose you mix two identical blocks of metal, one having a temperature of ${10}^{\circ }$ and the other ${20}^{\circ }$. Is it possible for the cold block to cool to ${5}^{\circ }C$ and the warm block to warm to ${25}^{\circ }C$?A. Yes, because it adheres to the second law of thermodynamics. B. No, because it will violate the zeroth law of thermodynamics. C. Yes, because it adheres to the zeroth law of thermodynamics. D. No, because it will violate the first law of thermodynamics.

Donna Flynn 2022-07-17

### An imaginary machine takes 9,000J of heat from a hot reservoir and 3,000 J of heat from a cold reservoir and produces 12,000 J of work. What can be said about this machine? O It violates both the first and second laws of thermodynamics. It violates the second law of thermodynamics but not the first law. It violates the first law of thermodynamics but not the second law. O It does not violate either the first or the second law of thermodynamics.

anudoneddbv 2022-07-15

### A superconducting ring can carry a current for an indeﬁ nite length of time. Isn’t this a perpetual motion machine, which violates the ﬁ rst or second law of thermodynamics? Explain.

Darryl English 2022-07-14