An insulated 8 m³ rigid tank contains air initially at 305K and 181 kPa. A 15 heater running off a constant 108.1 V power source is used to heat the air. The heater is turned on long enough for the pressure to increase to 362 kPa. a) How much boundary work is done? KJ b) How long must the heater remain on (accounting for the fact that the specific heat is not constant)? minutes c) How long must the heater remain on assuming the specific heat is constant at a value taken from 300K?

An insulated 8 m³ rigid tank contains air initially at 305K and 181 kPa. A 15 heater running off a constant 108.1 V power source is used to heat the air. The heater is turned on long enough for the pressure to increase to 362 kPa. a) How much boundary work is done? KJ b) How long must the heater remain on (accounting for the fact that the specific heat is not constant)? minutes c) How long must the heater remain on assuming the specific heat is constant at a value taken from 300K?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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