A single-phase two-winding transformer is rated 20 kVA, 480/…
A single-phase two-winding transformer is rated 20 kVA, 480/120 volts, 60 Hz. During a short-circuit test, where rated current at rated frequency is applied to the 480-volt winding (denoted winding 1), with the 120-volt winding (winding 2) shorted, the following readings are obtained: V1=35 volts, P1 = 300 W. During an open-circuit test, where rated voltage is applied to winding 2, with winding 1 open, the following readings are obtained: I2 =12 A, P2 = 200 W. Find the following: a. From the short-circuit test, determine the equivalent series impedance Zeq1 =Req1 + jXeq1 referred to winding 1. Neglect the shunt admittance. b. From the open-circuit test, determine the shunt admittance Ym = Gc jBm referred to winding 1. Neglect the series impedance.
Read DetailsIn recent years, energy producers have been at odds with act…
In recent years, energy producers have been at odds with activists who oppose the construction of new pipelines that could transport liquefied natural gas (LNG) to markets in the United States and abroad. Coalitions of citizens’ groups have voiced their concerns about the potential threat that new pipelines might pose to the environment and public safety. As a result, energy producers and the government have sought alternative ways to transport LNG within the confines of current law. In 2015 the United States Pipeline and HazardousMaterials Safety Administration (PHMSA) issued the first permit for transporting LNG by rail. This bureaucratic agency, which is part of the Department of Transportation, expanded the practice in 2017. Citizens’ groups voiced similar concerns about the transportation of LNG by rail but could not muster enough support in Congress for a new law. The presidential administration at the time responded to pressure from industry groups by supporting the expansion of permits, setting new rules and regulations to make it easier to transport LNG by rail. In 2019, without further direction from Congress, the PHMSA established new safety requirements and expanded the number of permits available. Respond to parts A, B, and C. A. Describe the power the bureaucratic agency used in the scenario. B. Explain how Congress could counteract the use of the power described in part A. C. Explain how the citizens’ groups in the scenario illustrate the concept of pluralist democracy.
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