Concept explainers
Check Your Understanding Figure 1.4 says the mass of the atmosphere is
How many piano tuners are there in New York City? How many leaves are on that tree? If you are studying photosynthesis or thinking of writing a smartphone app tot piano tuners, then the answers to these questions might be of great interest to you. Otherwise, you probably couldn’t care less what the answers are. However, these are exactly the soils of estimation problems that people in various tech industries have been asking potential employees to evaluate their quantitative reasoning skills. If building physical intuition and evaluating quantitative claims do not seem like sufficient reasons tot you to practice estimation problems, how about the fact that being good at them just might land you a high-paying job?
For practice estimating relative lengths, areas, and volumes, check out this PhET (https://openstaxcollege.org/l/21lengthgame) simulation, titled “Estimation.”
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Check out a sample textbook solutionChapter 1 Solutions
University Physics Volume 1
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- Paperweight I bought a pack of 100 rectangular index cards. Each card measured 15 by 10 cm. The pack said :Paper Density = 200 GSM (grams per square meter). This means that a square meter of those cards weighs 200 g. A) All of the cards in the pack are place flat on a table without overlap. In square meters, what is the total area of the table covered by the cards? B) Each pack of cards is wrapped in a sheet of 50 GSM paper with an area of 800cm squared. I have a number of packs and wish to store them on a shelf that cannot hold more than 10 kg. What is the largest whole number of wrapped packs that can be stored? C) The total weight of 500 identical sheets of paper is 2.4kg. If each sheet measures 30cm by 20cm, what is its paper density in GSM? D) A business card measures 55mm by 90mm. Its paper density is 300 GSM. Fins its exact weight in grams.arrow_forwardThe density of atmospheric air varies with elevation (2), decreasing with increasing altitude. a) Using the date given in Table 2, obtain a relation for the variation of density (p) with elevation (2). Assume the earth to be a perfect sphere with a radius (r) of 6377 km and the thickness of the atmosphere is 25 km as illustrated in Figure 1. b) Calculate the density of atmosphere air at an elevation of 7000 m. Atmosphere thickness = 25 km Earth radius, r= 6377 km www 6381 were 6382 Table 2: Density of atmosphere related to earth radius. Radius r, km 6377 6378 6379 6380 6383 6385 6387 6392 6397 6402 *r=z+6377 km Find density of air a Earth surface Density p. kg/m³ 1.225 1.112 7 km 1.007 0.9093 0.8194 0.7364 0.6601 0.5258 0.4135 0.1948 0.08891 0.04008arrow_forwardExplorers in the jungle find an ancient monument in the shape of a large isosceles triangle as shown in the figure below. The monument is made from tens of thousands of small stone blocks of density3 633kg/m3. The monument is16.7m high and68.5m wide at its base and is everywhere3.70m thick from front to back. Before the monument was built many years ago, all the stone blocks lay on the ground. How much work did laborers do on the blocks to put them in position while building the entire monument?Note: The gravitational potential energy of an object-Earth system is given byUg=MgyCM, whereMis the total mass of the object andyCMis the elevation of its center of mass above the chosen reference level.Jarrow_forward
- DEA agents watch drug smugglers load cocaine onto a fishing boat in a Mexican river to transport it down the river to the ocean, and then to Miami. To estimate how much cocaine was loaded, they measure how much further the boat sinks into the water after being loaded. If the boat’s area at the waterline is 50 m2 and it sinks by 2 cm, how much cocaine was loaded?arrow_forwardA hot tub with a surface area of 28 ft2 is filled with water to a depth of 29 in . Hint: volume is calculated as area × height (A × h). A) What is the volume of water in the tub, in liters? Express your answer to two significant figures and include the appropriate units. B) How many kilojoules are needed to heat the water from 59∘F to 103 ∘F? Express your answer to two significant figures and include the appropriate units. C) If the hot-tub heater provides 5900 kJ/min, how long, in hours, will it take to heat the water in the hot tub from 59∘F to 103∘F? Express your answer to two significant figures and include the appropriate units.arrow_forwardWe have a very large sheet of extremely thin paper. Assume that the paper is in fact only 0.1mm (0.0039 inches) thick. Imagine that this paper will be folded in half repeatedly, 50 times. Guess how thick the paper will be at the end! Quick metric system converter: 10mm=1cm (about 0.39 inches) 100cm=1meter ( about 3.3 feet) 1000m=1kilometer (about 0.62miles)arrow_forward
- Convert the volume (SCF) of natural gas to tons of natural gas. Given: volume of gas is 42,201 standard cubic feet (SCF) at 60°F and 14.7psia. NOTE: this answer will NOT be in metric tons, but English tons. Choose your answer with TWO decimals. O 1.60 10^5 tons O 3.20*10^8 tons O 1.11 tons O 2.78 10^-3 tonsarrow_forwardThe density of aluminum is 2.7 g/cm3g/cm3. What is the mass of a cube of aluminum that is 5.000 cmcm on a side? (Recall that density is mass divided by volume.)arrow_forwardIf 200 oak trees are counted on a 2 km x 2 km patch of land, what is the density of maple trees per square kilometer? What is the density of the oak trees per km2?arrow_forward
- College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University