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A monatomic ideal gas performs the cycle $1 \to 2 \to 3 \to 4 \to 1$ shown on the $p$–$V$ graph (see the figure): $1 \to 2$ is isochoric heating, $2 \to 3$ isobaric expansion, $3 \to 4$ isochoric cooling, $4 \to 1$ isobaric compression. On the graph the pressure is given in units of $10^5$ Pa and…
How much heat is needed to heat water of mass $m = 2$ kg from a temperature of $t_1 = 20°$C to $t_2 = 100°$C? The specific heat capacity of water is $c = 4200$ J/(kg·K).
Find the quantity of heat needed to melt ice of mass $m = 0.5$ kg at a temperature of $0°$C. The latent heat of fusion of ice is $\lambda = 3.4 \cdot 10^5$ J/kg.
The efficiency of a heat engine is $\eta = 40\%$. In one cycle the engine takes a quantity of heat $Q_1 = 1000$ J from the heater. Find the work done by the engine in one cycle.
Water of mass $m_1 = 2$ kg at a temperature of $t_1 = 80°$C is mixed with water of mass $m_2 = 3$ kg at a temperature of $t_2 = 20°$C. Find the temperature of the mixture. Neglect heat loss to the surroundings.
A gas absorbs a quantity of heat $Q = 500$ J and at the same time does work $A = 200$ J. Find the change in internal energy of the gas.
A gas is heated isobarically (at constant pressure) from a temperature $T_1 = 300$ K to $T_2 = 450$ K. The initial volume of the gas is $V_1 = 2$ L. Find the final volume of the gas.
An ideal gas at pressure $p = 2 \cdot 10^5$ Pa and temperature $T = 300$ K occupies a volume $V = 0.01$ m³. Find the amount of substance of the gas. The universal gas constant is $R = 8.31$ J/(mol·K).