Introduction To Health Physics
5th Edition
ISBN: 9780071835275
Author: Johnson, Thomas E. (thomas Edward), Cember, Herman.
Publisher: Mcgraw-hill Education,
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Chapter 2, Problem 2.38P
How much sub-butuminous coal (20,000 kJ/kg) would it take to generate the electricity needed to keep a 100 W light bulb lit for 1 year if the overall efficiency of the generating station is 30%?
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In a particular town, electrical energy costs $0.12 per kilowatt-hour. (Round your answers, in dollars, to at least two decimal places.)
(a) How much does it cost to operate an old-style incandescent 100-W light bulb continuously for 24 hours?
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(b) A modern LED light bulb that emits as much visible light as a 100-W incandescent only draws 16.0 W of power. How much does it cost to operate this bulb for 24 hours?
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The 20-W LED bulb can provide the same amount of light output as the 100-W incandescent light bulb. How much percentage you could save for using the LED bulb in place of the incandescent bulb for one year, assuming ₱7.50 per kilowatt-hour is the average energy rate charged by the power company? Assume that the bulb is turned on for 7 hours a day.
a.) 20%
b.) 80%
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A typical incandescent reading lamp runs at 60W. If it is lefton constantly, how much energy (J) is consumed per day,and what is the weekly cost if energy is charged at a rate of12.5 cents per kilowatthour?
Chapter 2 Solutions
Introduction To Health Physics
Ch. 2 - Two blocks of mass 0.1 kg and 0.2 kg approch each...Ch. 2 - A bullet whose mass is 50 g travels at a velocity...Ch. 2 - Compute the mass of the Earth, assuming it to be a...Ch. 2 - An automobile weighing 2000 kg and going at a...Ch. 2 - A small electrically charged sphere of mass 0.1 g...Ch. 2 - A capacitor has a capacitance of 10F . How much...Ch. 2 - A small charged particle whose mass is 0.01 g...Ch. 2 - Prob. 2.8PCh. 2 - Prob. 2.9PCh. 2 - Prob. 2.10P
Ch. 2 - Prob. 2.11PCh. 2 - Prob. 2.12PCh. 2 - Prob. 2.13PCh. 2 - Prob. 2.14PCh. 2 - Prob. 2.15PCh. 2 - A current of 25 mA flows through a 25-gauge wire,...Ch. 2 - An electron starts at rest on the negative plate...Ch. 2 - Prob. 2.18PCh. 2 - Prob. 2.19PCh. 2 - Prob. 2.20PCh. 2 - Prob. 2.21PCh. 2 - Prob. 2.22PCh. 2 - Prob. 2.23PCh. 2 - (a) A 1000-MW(e) nuclear power plant operates at a...Ch. 2 - Prob. 2.25PCh. 2 - Prob. 2.26PCh. 2 - Prob. 2.27PCh. 2 - The specific heat of water in the English system...Ch. 2 - Prob. 2.29PCh. 2 - Prob. 2.30PCh. 2 - Prob. 2.31PCh. 2 - Prob. 2.32PCh. 2 - How many cubic meters of water must fall over a...Ch. 2 - (a) Calculate the speed of a 25-MeV proton. (b)...Ch. 2 - Prob. 2.35PCh. 2 - Prob. 2.36PCh. 2 - Calculate the speed of a (a) 0.5-MeV electron and...Ch. 2 - How much sub-butuminous coal (20,000 kJ/kg) would...Ch. 2 - Prob. 2.40PCh. 2 - How much oil (138,690 Btu/gal) would it take to...Ch. 2 - How much oil (138,690 Btu/gal) would it take to...Ch. 2 - Prob. 2.43PCh. 2 - Prob. 2.44PCh. 2 - Prob. 2.45PCh. 2 - Prob. 2.46PCh. 2 - Prob. 2.47PCh. 2 - Prob. 2.48PCh. 2 - Prob. 2.49P
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