A 10 Ω resistor is held at a temperature of 300 K. A current of 5 A is passed through the resistor for 2 minutes. Ignoring changes in the source of the current, what is the change of entropy in (a) the resistor and (b) the Universe?

In1816, Robert Stirling, a Scottish clergyman , patented the Stirling engine which has found a wide variety of applications ever since, including current use in solar energy collectors to transform sunlight into electricity. Fuel is burned externally to warm one of the engine's two cylinders, A fixed quantity of inert gas moves cyclically between the cylinders, expanding in the hot one and contracting in the cold one. Figure P21.33 represents a model for its thermodynamic cycle. Consider n moles of an ideal monoatomic gas being taken once through the cycle, consisting of two isothermal processes at temperatures 3Tiand Ti and two constant-volume processes. Let us find the efficiency of this engine .(a) Find the energy transferred by heat into gas during the isovolumetric process AB. (b) Find the energy transferred by heat into the gas during the isothermal process BC. (c) Find the energy transferred by heat into the gas during isovolumetric process CD. (d) Find the enrgy transferred by…

A 310 cm3 cup of coffee cools from 88∘C to the 20∘C temperature of the room. Assume that the temperature of the room does not change and coffee has the same specific heat and density as water. What is the entropy change of the coffee? Of the room? Of the universe

If you are told that the entropy of a system is zero, what do you know about the system?