1.
Prin sistem termodinamic se înțelege un ansamblu bine precizat de corpuri macroscopice.
Correct Answer
A. True
Explanation
The statement is true because the term "sistem termodinamic" refers to a well-defined ensemble of macroscopic bodies. This means that it involves a collection of objects or substances that can be observed and measured on a large scale, such as a system of gases or a container of liquid. In thermodynamics, the focus is on the behavior of these macroscopic systems and their interactions, rather than the individual particles or atoms that make them up. Therefore, the given statement accurately describes the concept of a thermodynamic system.
2.
Starea unui sistem termodinamic reprezintă totalitatea proprietăților sistemului termodinamic la un moment dat.
Correct Answer
A. True
Explanation
The statement is true because the state of a thermodynamic system refers to the combination of all its properties at a given moment. These properties include variables such as temperature, pressure, volume, and composition. By knowing the state of a system, one can determine its behavior and predict how it will respond to changes in its surroundings. Therefore, the statement accurately describes the concept of the state of a thermodynamic system.
3.
Parametrii de stare sunt mărimi fizice măsurabile care caracterizează starea sistemului termodinamic la un moment dat.
Correct Answer
A. True
Explanation
The statement is true because parametrii de stare (state parameters) are measurable physical quantities that describe the state of a thermodynamic system at a given moment. These parameters can include variables such as temperature, pressure, volume, and mass, which provide information about the system's properties and behavior. Therefore, the statement accurately describes the nature and purpose of state parameters in thermodynamics.
4.
Un sistem termodinamic este închis dacă schimbă energie și substanță cu mediul exterior.
Correct Answer
B. False
Explanation
deschis
5.
Volumul de gaz cuprins într-un cilindru în care se deplasează fără frecare un piston este un exemplu de sistem termodinamic.
Correct Answer
A. True
Explanation
The given statement is true because a system that consists of a gas volume enclosed by a piston in a cylinder is an example of a thermodynamic system. In thermodynamics, a system refers to a specific region or substance under consideration, and in this case, it is the gas volume enclosed by the piston. The movement of the piston without friction allows for the transfer of energy between the gas and its surroundings, making it a thermodynamic system.
6.
Un atom este un sistem termodinamic deoarece conține un număr foarte mic de particule.
Correct Answer
B. False
Explanation
An atom is not a thermodynamic system because it is a single particle and does not contain a large number of particles. In thermodynamics, a system refers to a collection of particles or substances that are being studied. Since an atom is a single entity, it does not meet the criteria of a thermodynamic system.
7.
Universul nu este un sistem termodinamic deoarece este infinit.
Correct Answer
A. True
Explanation
The explanation for the given correct answer is that the universe is not a thermodynamic system because it is infinite. Thermodynamic systems have boundaries and interact with their surroundings, but since the universe is infinite, it does not have a defined boundary and cannot interact with anything outside of itself. Therefore, it does not fit the criteria of a thermodynamic system.
8.
Energia internă este o mărime fizică de
Correct Answer
stare.
Explanation
The correct answer is "stare" because energia internă is a physical quantity that describes the internal energy of a system. It is a measure of the total energy of all the particles within the system, including their kinetic and potential energies. The word "stare" in Romanian translates to "state" in English, which refers to the condition or state of the system. Therefore, the correct answer is "stare" as it accurately represents the concept of energia internă.
9.
Mărimea fizică numeric egală cu căldura necesară modificării temperaturii unui corp cu se numește:
Correct Answer
C. Capacitate calorică;
Explanation
The correct answer is "capacitate calorică". Capacitatea calorică este o mărime fizică care reprezintă cantitatea de căldură necesară pentru a modifica temperatura unui corp cu o unitate de temperatură. Este o mărime specifică fiecărui corp și poate fi exprimată în diferite unități, cum ar fi jouli pe grad Celsius sau calorii pe grad Celsius.
10.
Știind că simbolurile mărimilor fizice sunt cele utilizate în manualele de fizică, unitatea de măsură a energiei interne în S.I. este:
Correct Answer
B. J;
Explanation
The correct answer is J. In physics, the symbol for energy is typically represented by the letter "E". The unit of measurement for energy in the International System of Units (SI) is the Joule (J). Therefore, the correct answer is J.
11.
Știind că simbolurile mărimilor fizice sunt cele utilizate în manualele de fizică, lucrul mecanic într-o transformare în care volumul gazului ideal rămâne constant are expresia:
Correct Answer
B. L=0
Explanation
The correct answer is L=0. In a transformation where the volume of an ideal gas remains constant, no work is done. Therefore, the value of work done (L) is zero.
12.
Învelișul adiabatic nu permite:
Correct Answer
C. Schimbul de căldură între sistem și mediul exterior;
Explanation
The adiabatic envelope does not allow for the exchange of heat between the system and the external environment. An adiabatic process is one in which there is no heat transfer into or out of the system, meaning that the system is thermally isolated. Therefore, the adiabatic envelope prevents any heat exchange between the system and the external environment, ensuring that the system's internal energy remains constant.
13.
Notațiile folosite fiind cele obișnuite în manualele de fizică, relația lui Robert-Mayer pentru călduri molare poate fi scrisă:
Correct Answer
B. Cp=Cv+R
Explanation
The correct answer is Cp=Cv+R. This equation represents Robert-Mayer's relationship for molar heat capacities in physics. It states that the molar heat capacity at constant pressure (Cp) is equal to the molar heat capacity at constant volume (Cv) plus the gas constant (R). This equation is commonly used in thermodynamics to relate the heat capacities of gases at different conditions.