Lesson Menu Print NAME ______________________________________ DATE _______________ CLASS ____________________ Holt Physics Problem 1A METRIC PREFIXES PROBLEM In Hindu chronology, the longest time measure is a para. One para equals 311 040 000 000 000 years. Calculate this value in megahours and in nanoseconds. Write your answers in scientific notation. SOLUTION Given: 1 para = 311 040 000 000 000 years Unknown: 1 para = ? Mh 1 para = ? ns Express the time in years in terms of scientific notation. Then build conversion factors from the relationships given in Table 1-3. 1 para = 3.1104 × 1014 years 24 h 1 Mh 365.25 days × × 1 day 1 × 106 h 1 year 24 h 1 ns 365.25 days 3600 s × × × 1 day 1 × 10−9s 1 year 1h HRW material copyrighted under notice appearing earlier in this book. Convert from years to megahours by multiplying the time by the first conversion expression. 1 Mh 365.25 days 24 h 1 para = 3.1104 × 1014 years × × × 1 day 1 × 106 h 1 year = 2.7266 × 1012 Mh Convert from years to nanoseconds by multiplying the time by the second conversion expression. 1 ns 365.25 days 24 h 3600 s 1 para = 3.1104 × 1014 years × × × × 1 year 1 day 1h 1 × 10−9 s = 9.8157 × 1030 ns ADDITIONAL PRACTICE 1. One light-year is the distance light travels in one year. This distance is equal to 9.461 × 1015 m. After the sun, the star nearest to Earth is Alpha Centauri, which is about 4.35 light-years from Earth. Express this distance in a. megameters. b. picometers. Problem 1A 1 Menu Lesson Print NAME ______________________________________ DATE _______________ CLASS ____________________ 2. It is estimated that the sun will exhaust all of its energy in about ten billion years. By that time, it will have radiated about 1.2 × 1044 J (joules) of energy. Express this amount of energy in a. kilojoules. b. nanojoules. 3. The smallest living organism discovered so far is called a mycoplasm. Its mass is estimated as 1.0 × 10–16 g. Express this mass in a. petagrams. b. femtograms. c. attograms. 4. The “extreme” prefixes that are officially recognized are yocto, which indicates a fraction equal to 10–24, and yotta, which indicates a factor equal to 1024. The maximum distance from Earth to the sun is 152 100 000 km. Using scientific notation, express this distance in a. yoctometers (ym). b. yottameters (Ym). 5. In 1993, the total production of nuclear energy in the world was 2.1 × 1015 watt-hours, where a watt is equal to one joule (J) per second. Express this number in 6. In Einstein’s special theory of relativity, mass and energy are equivalent. An expression of this equivalence can be made in terms of electron volts (units of energy) and kilograms, with one electron volt (eV) being equal to 1.78 × 10–36 kg. Using this ratio, express the mass of the heaviest mammal on earth, the blue whale, which has an average mass of 1.90 × 105 kg, in a. mega electron volts. b. tera electron volts. 7. The most massive star yet discovered in our galaxy is one of the stars in the Carina Nebula, which can be seen from Earth’s Southern Hemisphere and from the tropical latitudes of the Northern Hemisphere. The star, designated as Eta Carinae, is believed to be 200 times as massive as the sun, which has a mass of nearly 2 × 1030 kg. Find the mass of Eta Carinae in a. milligrams. b. exagrams. 8. The Pacific Ocean has a surface area of about 166 241 700 km2 and an average depth of 3940 m. Estimate the volume of the Pacific Ocean in a. cubic centimeters. b. cubic millimeters. 2 Holt Physics Problem Workbook HRW material copyrighted under notice appearing earlier in this book. a. joules. b. gigajoules. Menu Lesson Print The Science of Physics Chapter 1 Additional Practice 1A Givens 1. distance = 4.35 light years Solutions 9.461 × 1015 m distance = 4.35 light years × = 4.12 × 1016 m 1 light year 1 Mm a. distance = 4.12 × 1016 m × 6 = 4.12 × 1010 Mm 10 m 1 pm = 4.12 × 1028 pm b. distance = 4.12 × 1016 m × 10−12 m 2. energy = 1.2 × 1044 J 1 kJ a. energy = 1.2 × 1044 J × = 1.2 × 1041 kJ 103 J II 1 nJ b. energy = 1.2 × 1044 J × − = 1.2 × 1053 nJ 10 9 J 3. m = 1.0 × 10−16 g 1 Pg a. m = 1.0 × 10−16 g × 1 = 1.0 × 10−31 Pg 10 5 g 1 fg b. m = 1.0 × 10−16 g × −1 = 0.10 fg 10 5 g 1 ag c. m = 1.0 × 10−16 g × −1 = 1.0 × 102 ag 10 8 g Copyright © by Holt, Rinehart and Winston. All rights reserved. 4. distance = 152 100 000 km 1000 m 1 ym = 1.521 × 1035 ym a. distance = 152 100 000 km × × 1 km 10−24 m 1000 m 1 Ym b. distance = 152 100 000 km × × 24 = 1.521 × 10−13 Ym 1 km 10 m 5. energy = 2.1 × 1015 W • h 1 J/s 3600 s a. energy = 2.1 × 1015 W • h × × = 7.6 × 1018 J 1W 1h 1 GJ b. energy = 7.6 × 1018 J × = 7.6 × 109 GJ 109 J 6. m = 1.90 × 105 kg 1 eV m = 1.90 × 105 kg × = 1.07 × 1041 eV 1.78 × 10−36 kg 1 MeV a. m = 1.07 × 1041 eV × 6 = 1.07 × 1035 MeV 10 eV 1 TeV = 1.07 × 1029 TeV b. m = 1.07 × 1041 eV × 1012 eV Section Two — Problem Workbook Solutions II Ch. 1–1 Menu Lesson Print Givens Solutions 7. m = (200)(2 × 1030 kg) = 4 × 1032 kg 103 g 103mg a. m = 4 × 1032 kg × × = 4 × 1038 mg 1 kg 1g 1 Eg 103 g b. m = 4 × 1032 kg × × 1 = 4 × 1017 Eg 10 8 g 1 kg 8. area = 166 241 700 km2 depth = 3940 m V = volume = area × depth 17 2 1000 m V = (166 241 700 km2)(3940 m) × 1 km 3 V = 6.55 × 10 m 106 cm3 a. V = 6.55 × 1017 m3 × = 6.55 × 1023 cm3 1 m3 109 mm3 b. V = 6.55 × 1017 m3 × = 6.55 × 1026 mm3 1 m3 Copyright © by Holt, Rinehart and Winston. All rights reserved. II II Ch. 1–2 Holt Physics Solution Manual