Podcast
Questions and Answers
What is the ratio of useful work obtained from the engine to the heat supplied to it?
What is the ratio of useful work obtained from the engine to the heat supplied to it?
- Work done W
- Heat input Q1
- Thermodynamic efficiency η (correct)
- Heat output Q2
What is the result of the first law of thermodynamics for a cyclic process?
What is the result of the first law of thermodynamics for a cyclic process?
- ΔU = Q1
- ΔU = W
- ΔU = Q2
- ΔU = 0 (correct)
What is the fundamental principle underlying the efficiency of a Carnot engine?
What is the fundamental principle underlying the efficiency of a Carnot engine?
- Efficiency is directly proportional to the heat input
- Efficiency is independent of the volume of the system
- Heat input is always equal to work output
- Temperatures of source and sink determine the efficiency (correct)
What is the characteristic of a perfect heat engine?
What is the characteristic of a perfect heat engine?
Which statement is a direct consequence of the second law of thermodynamics?
Which statement is a direct consequence of the second law of thermodynamics?
What is the relation between the temperatures of the source and sink in a Carnot engine?
What is the relation between the temperatures of the source and sink in a Carnot engine?
What is the purpose of a refrigerator or heat pump?
What is the purpose of a refrigerator or heat pump?
Which statement is true about the efficiency of an actual engine?
Which statement is true about the efficiency of an actual engine?
What is the definition of the efficiency of a heat engine?
What is the definition of the efficiency of a heat engine?
What is the condition for a reversible heat engine to be equally efficient?
What is the condition for a reversible heat engine to be equally efficient?
What is the coefficient of performance of a perfect refrigerator?
What is the coefficient of performance of a perfect refrigerator?
What is the relation between the coefficient of performance and the efficiency of a refrigerator?
What is the relation between the coefficient of performance and the efficiency of a refrigerator?
What is the condition for the coefficient of performance to be zero?
What is the condition for the coefficient of performance to be zero?
What does the first law of thermodynamics explain?
What does the first law of thermodynamics explain?
What is the expression for the coefficient of performance of a Carnot refrigerator?
What is the expression for the coefficient of performance of a Carnot refrigerator?
What is the approximate height a person can climb if they gain 105 calories of heat energy from food and their body's efficiency is 28%?
What is the approximate height a person can climb if they gain 105 calories of heat energy from food and their body's efficiency is 28%?
If a hailstone at 0°C falls from a height of 1 km on an insulating surface, converting its kinetic energy into heat, what fraction of it will melt?
If a hailstone at 0°C falls from a height of 1 km on an insulating surface, converting its kinetic energy into heat, what fraction of it will melt?
A bullet moving with a uniform velocity stops suddenly after hitting a target and its whole mass melts. If the initial temperature is 25°C, the melting point is 475°C, and the latent heat is L, what is the correct equation?
A bullet moving with a uniform velocity stops suddenly after hitting a target and its whole mass melts. If the initial temperature is 25°C, the melting point is 475°C, and the latent heat is L, what is the correct equation?
What is the unit of the energy required to melt a certain amount of substance?
What is the unit of the energy required to melt a certain amount of substance?
If a person's body is at a temperature of 25°C and they gain 105 calories of heat energy from food, what is the approximate increase in their potential energy?
If a person's body is at a temperature of 25°C and they gain 105 calories of heat energy from food, what is the approximate increase in their potential energy?
What is the unit of mechanical equivalent of heat J?
What is the unit of mechanical equivalent of heat J?
If a bullet of mass m and velocity v is fired from a gun and strikes a target, what is the rise in temperature of the bullet?
If a bullet of mass m and velocity v is fired from a gun and strikes a target, what is the rise in temperature of the bullet?
What is the expression for the potential energy of water in a stream falling from a height h?
What is the expression for the potential energy of water in a stream falling from a height h?
What is the value of the mechanical equivalent of heat J in kilocalorie?
What is the value of the mechanical equivalent of heat J in kilocalorie?
What is the significance of the mechanical equivalent of heat J?
What is the significance of the mechanical equivalent of heat J?
For an ideal gas, if the pressure is constant, then what is the ratio of the heat energy used in doing external work to the total heat energy given?
For an ideal gas, if the pressure is constant, then what is the ratio of the heat energy used in doing external work to the total heat energy given?
What is the change in internal energy of a system if the latent heat of vaporization of water is 2240 J/g and the work done in the process of expansion of 1g is 168 J?
What is the change in internal energy of a system if the latent heat of vaporization of water is 2240 J/g and the work done in the process of expansion of 1g is 168 J?
For an ideal gas, if the adiabatic index is 5/3, then what is the ratio of the specific heat at constant pressure to the specific heat at constant volume?
For an ideal gas, if the adiabatic index is 5/3, then what is the ratio of the specific heat at constant pressure to the specific heat at constant volume?
If the volume of 1kg of water at 100°C is 10^(-3) m^3 and the volume of 1 kg of steam at normal pressure is 1.671 m^3, then what is the density of the steam?
If the volume of 1kg of water at 100°C is 10^(-3) m^3 and the volume of 1 kg of steam at normal pressure is 1.671 m^3, then what is the density of the steam?
If the heat given to a gas is 1050 calorie, and R = 2 cal/mole degree, then what is the change in temperature of the gas?
If the heat given to a gas is 1050 calorie, and R = 2 cal/mole degree, then what is the change in temperature of the gas?
