Suppose you have two kettles --a plug-in electric kettle and a stovetop kettle. The electric kettle uses electricity from a natural gas fired powerplant, while you boil water in your stovetop kettle on a natural gas burner. Based on the following information, which of these kettles demonstrates a higher energy efficiency? Please calculate the efficiencies of each kettle and express answers as percentages   -The natural gas power plant converts chemical energy of the natural gas to electrical energy with 58% efficiency. -High-voltage power lines from the power plant to your house convey electricity with 92% efficiency. -The electric kettle converts electrical energy to thermal energy in the water with 85% efficiency. -The stove burner converts chemical energy of natural gas to thermal energy with 98% efficiency (the other 2% is light). -The stovetop kettle transfers 35% of the stove’s thermal energy to the water in the kettle.

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Q: A refrigerating machine is driven by a motor of output power 2.25 kW and 2.5 tons of ice at -7°C…

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Q: A 600-MW steam power plant, which is cooled by a nearby river, has a thermal efficiency of 40…

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Q: The work done during the expansion of a gas is 5.31 kJ. The relationship between the pressure and…

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Q: In an analysis, a heat engine based on the Carnot cycle operating between 1000 0C and 300 0C. The…

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Q: 1) Provide equations that best match the following: • Total boundary work • Boundary work for a…

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Q: 4. You are told the initial and final states of a system and the associated change in internal…

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Q: - Air entering an adiabatic gas turbine with a mass flow of 24 kg/s, leaves the turbine with a…

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Q: Carnot engine operating between 775 0K and 305 0K produces 54 kJ of work. Determine (a) QA, (b) S…

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Q: Q3/ A Carnot heat engine receives 655 k. of unknown temperature and rejects 245 kJ Determine (a) the…

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Q: A gaseous Ammonia actuates a Carnot power cycle in which the respective volumes at the four corners…

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Q: and 600 c. the condenser pressure is 15 kpa. the turbine and pump isentropic efficiencies are 95 %…

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Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.