Problem 3 A power plant produces 1500 MWe with an efficiency of 35 %. Assuming this is a coal-fired plant, (a) calculate how much bituminous coal does it burn in an hour? (b) Estimate how much heat in Joules is released to the environment per second? Assume that the energy content of bituminous coal is 31 MJ/kg.

Suppose you spend 30.0 minutes on a stair-climbing machine, climbing at a rate of 65 steps per minute, with each step 8.00 inches high. If you weigh 150 lb and the machine reports that 750 kcal have been burned at the end of the workout, what efficiency is the machine using in obtaining this result? %If your actual efficiency is 0.19, how many kcal did you really burn? kcal

35. A refrigerator consumes 294 KWh of electricity per year. Determine the primary energy requirements in units of MMBTU for the refrigerator assuming: a. The electricity came from a coal power plant with an efficiency of 32%. b. The electricity came from a natural gas plant with an efficiency of 44%.

em 5 A NATO base in northern Norway is warmed with a heat pump that uses 7.0°C ocean water as the cold reservoir, Heat extracted from the ocean water warms fluid to 80° C; this warmed fluid is used to heat the building When the system is working at full capacity, 2000 kW of heat are delivered to the building at the cost of 600 kW of electric energy. Part A What is the actual coefficient of performance of the system? COP Submit Request Answer Part B What is the theoretical maximum coefficient of performance of the system? COPX Submit Request Answar P Type here to search

A heat engine takes in 14 kJ of energy and rejects 6 kJ to a low temperature sink. 1. How much work does the engine produce?  2. What is the efficiency of the heat engine?

1st and 2nd Law of thermodynamics Worksheet 1. A car engine deliver 8.2 kJ of work per cycle. Its efficiency is 25%. A) How much heat is absorbed and how much heat is exhausted from its fuel combustion? B) The car is now tuned and its efficiency goes to 31%. What are the new values of heat absorbed and heat exhausted? 1 of 3

Steam locomotives have an efficiency of 15.0% and operate with a hot steam temperature of 475°C. (a) What would the cold reservoir temperature (in °C) be if this were a Carnot engine? °C (b) What would the maximum efficiency of this steam engine be if its cold reservoir temperature were 150°C? % Additional Materials B Reading ds Scanned with CamScanner

A certain coal-fired power plant has a rated power capacity of P = 850 MW. The output of this plant is W = 0.21QH, where QH is the energy input as heat from the hot reservoir. a) Which would increase the efficiency more, doubling QH or reducing QC by half?  b) Calculate the maximum thermal efficiency of the power plant.  c) Calculate the absolute value of the exhausted heat (QC) each second in MJ for the power plant.  d) If the power plant operates for a full day at its rated capacity, how much energy QH in MJ is needed?  e) If, on average, one ton of coal contains Q = 25 GJ of energy, how many tons nH of coal would the plant need to operate for a day at its rated capacity?  f) How many tons nC of this coal is exhausted as wasted heat to QC in a single day?