The “Energy Guide” label on a washing machine indicates that the washer will use $85 worth of hot water per year if the water is heated by an electric water heater at an electricity rate of $0.113/kWh. If the water is heated from 12 to 55°C, determine how many liters of hot water an average family uses per week. Disregard the electricity consumed by the washer, and take the efficiency of the electric water heater to be 91 percent.

Q: You observe a grasshopper eating a blade of grass. You know that each blade of grass contains 100…

A: Given that:- Energy contain in one blade of grass=100 units

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Q: (a) How much heat transfer occurs to the environment by an electrical power station that uses…

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Q: An electrical power station uses 1.58 x 1014 J of heat Input with an efficiency of 35.7%. (a) How…

A:

Q: In each cycle of its operation, a heat engine expels 2,900 J of energy and performs 1,600 J of…

A: energy expelled = 2900 J work done = 1600 J a) thermal energy that must be added to engine in each…

Q: heat engine operates between a hot reservoir at 790°C and a cold reservoir at a temperature of 15…

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Q: gasoline engine is running, an amount of gasoline containing 11,700 J of chemical potential energy…

A: Efficiency =W/Q

Q: In each cycle of its operation, a heat engine expels 5,900 J of energy and performs 1,700 J of…

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Q: As a gasoline engine is running, an amount of gasoline containing 16,000 J of chemical potential…

A: The work done by the engine, W=4000 J   The input chemical energy, Einput=16000 J

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Q: A heat engine receives heat in the amount of Qh = 775 kJ from a high temperature thermal reservoir…

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Q: 1. A coal-fired power plant produces 9.00 × 1013 J of electrical energy in one day, and operates…

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Q: A weight lifter bench‑presses a 150.0 kg barbell from his chest to a height equal the length of his…

A: Solution:   Given Values, Mass of barbell (m)=150 KgHeight (h)=0.850 m

Q: As a gasoline engine is running, an amount of gasoline containing 11,100 J of chemical potential…

A: Given Data: The input energy is: Qi=11100 J The output energy is: Qo=3700 J

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A:

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Q: A certain coal-fired power plant has a rated power capacity of P = 850 MW. The output of this plant…

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Q: If 40 million Joules of energy is put into the hot reservoir and the engine transfers 22 million…

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Q: As a gasoline engine is running, an amount of gasoline containing 18,500 J of chemical potential…

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Q: In order to keep a basement from flooding, it is necessary to pump 285 kg of water each minute from…

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Q: A certain coal-fired power plant has a rated power capacity of P = 1350 MW. The output of this plant…

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Q: The bulldozer for the road widening project has a gasoline engine that takes 10,000 J of heat and…

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Q: To produce 96 hp of mechanical power, an automobile engine requires a supply of heat of 4.91  105 J…

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