Thermodynamics CBSE Questions & Answers

A steam engine has a boiler that operates at 500 K. The energy from the burning fuel changes water to steam, and this steam then drives a piston. The cold reservoir’s temperature is that of the outside air, approximately 300 K. What is the maximum thermal efficiency of this steam engine?

The highest theoretical efficiency of a certain engine is 30 percent. If this engine uses the atmosphere, which has a temperature of 300 K, as its cold reservoir, what is the temperature of its hot reservoir?

One of the most efficient engines ever built (actual efficiency 42.0 percent) operates between 430\(^\circ \)C and 1 870\(^\circ \)C. What is its maximum theoretical efficiency?

One of the most efficient engines ever built (actual efficiency 42.0 percent) operates between 430\(^\circ \)C and 1 870\(^\circ \)C. How much power does the engine deliver if it absorbs1.40 \( \times \) \({\rm{1}}{0^{\rm{5}}}\) J of energy each second from the hot reservoir?

A Carnot engine has a power output of 150 kW. The engine operates between two reservoirs at 20.0\(^\circ \)C and 500\(^\circ \)C. How much energy does it absorb per hour?

A Carnot engine has a power output of 150 kW. The engine operates between two reservoirs at 20.0\(^\circ \)C and 500\(^\circ \)C. How much energy is lost per hour in its exhaust?

An ideal gas is taken through a Carnot cycle. The isothermal expansion occurs at 250\(^\circ \)C, and the isothermal compression takes place at 50.0\(^\circ \)C. Assuming that the gas absorbs 1 200 J of energy from the hot reservoir during the isothermal expansion, find the energy expelled to the cold reservoir in each cycle

An ideal gas is taken through a Carnot cycle. The isothermal expansion occurs at 250\(^\circ \)C, and the isothermal compression takes place at 50.0\(^\circ \)C. Assuming that the gas absorbs 1 200 J of energy from the hot reservoir during the isothermal expansion, find the net work done by the gas in each cycle

A power plant operates at 32.0 percent efficiency during the summer when the sea water for cooling is at 20.0\(^\circ \)C. The plant uses 350\(^\circ \)C steam to drive turbines. Assuming that the plant’s efficiency changes in the same proportion as the ideal efficiency, what would be the plant’s efficiency in the winter, when the sea water is at 10.0\(^\circ \)C?

A power plant that would make use of the temperature gradient in the ocean has been proposed. The system is to operate between 5.00\(^\circ \)C (water temperature at a depth of about 1 km) and 20.0\(^\circ \)C (surface water temperature).What is the maximum efficiency of such a system?

A power plant that would make use of the temperature gradient in the ocean has been proposed. The system is to operate between 5.00\(^\circ \)C (water temperature at a depth of about 1 km) and 20.0\(^\circ \)C (surface water temperature).If the power output of the plant is 75.0 MW, how much energy is absorbed per hour?

A typical dorm room or bedroom contains about 2500 moles of air. Find the change in the internal energy of this much air when it is cooled from 35.0\(^\circ \)C to 26.0\(^\circ \)C at a constant pressure of 1.00 atm. Treat the air as an ideal gas with γ = 1.4

A Carnot engine takes 2000 J of heat from a reservoir at 500 K, does some work, and discards some heat to a reservoir at 350 K. How much work does it do?

A Carnot engine takes 2000 J of heat from a reservoir at 500 K, does some work, and discards some heat to a reservoir at 350 K. How much heat is discarded?

A Carnot engine takes 2000 J of heat from a reservoir at 500 K, does some work, and discards some heat to a reservoir at 350 K. what is its efficiency?