In each of the following cases, a value of the desired quantity has been determined in some way, resulting in a number displayed on a calculator or computer screen. Your task is to round each number to a reasonable number of significant digits—up if a higher value is conservative, down if a lower value is conservative, and to the nearest value if it does not make a difference. Specify why your assumption is conservative.
(a) | The mass of an adult human riding on an elevator | 178.8 pounds |
(b) | The amount of milk needed to fill a cereal bowl | 1.25 cups |
(c) | The time it takes to sing Happy Birthday | 32.67 seconds |
Want to see the full answer?
Check out a sample textbook solutionChapter 5 Solutions
Thinking Like an Engineer: An Active Approach, Student Value Edition Plus MyLab Engineering with Pearson eText - Access Card Package (4th Edition)
Additional Engineering Textbook Solutions
Mechanics of Materials, 7th Edition
Mechanics of Materials
Machine Elements in Mechanical Design (6th Edition) (What's New in Trades & Technology)
Machine Tool Practices (10th Edition)
DESIGN OF MACHINERY
Vector Mechanics for Engineers: Statics
- According to the National Wildlife Federation, the polar bear is the largest terrestrial carnivore on Earth. Interestingly, these heavy bears spend much of their time roaming on frozen tundra and remarkably thin ice. Assume a polar bear weighs 980 pounds-force . The polar bear has a circular paw circumference of 37.7 inches . Determine the pressure the ice must be able to withstand if the polar bear is standing on its hind legs such that only two paws are in contact with the ice, in units of pounds-force per square inch .arrow_forwardIf under standard conditions a certain gas weighs 0.14 lb/ft^3, then its corresponding density. expressed in terms of slug per cubic feet (slug/ft^3), must bearrow_forwardNASA sent a probe to Saturn's moon Titan, where the acceleration due to gravity is 1.4 meters per second squared [ms2]. Titan's atmospheric pressure is 1.3 times Earth's atmospheric pressure at sea level. The probe landed in a lake of liquid methane, which has a density of 0.454 kilograms per liter [kgL]. Since the probe weighs 300 pounds-force [lbf] on Titan and has a volume of only 1.2 cubic feet [ft3], it immediately sank. It now sits 65 feet [ft] below the surface of the lake. The lake has a surface area exposed to the atmosphere of 24500 square meters [m2]. What is the total pressure exerted on the probe, in pascals [Pa]?arrow_forward
- When the motion between two elements of a pair is possible in more than....................direction and depends upon the direction of the force applied, it is known as incompletely constrained motion.arrow_forward1. A special-purpose piece of laboratory glassware, called a pyncnometer; is used to measureLiquid densities. It has a volume of 25 cc, and a mass of 17 .24 g when it is full of air. Whenfilled with a liquid of unknown density, its mass = 45.00 g. What is the density of this liquid?How large an error do we make if we ignore the mass of the air that was in it when we weighed itand found m = 17.24 g?arrow_forwardGraph below represents the force on a 12 kg air mass as it passes through a jet engine. Immediately after entering the engine, the force is 9,039 N, and the force tapers linearly to zero once the air reaches the back of the engine 2.3 m later. If the air enters the engine with velocity 252 m/s, what is its exit velocity? (Please answer to the fourth decimal place - i.e 14.3225)arrow_forward
- Please answer the following question A cigarettes dispenser requires a south African five-rand (R5) coin with a mass of 9.5 g to dispense one cigarette with a mass of 0.2 g. The design of such a cigarette dispenser is based on a helical spring, of negligible mass, which is found to extend 0.1 mm under a mass of 0.2 g. The spring can support a total mass of a coin. As the customer place money on the dispenser, the spring and coin system displace vertically through 4 mm and release. 1.1. Provide a schematic representation of the mass and spring system. 1.2. Calculate the frequency of natural vibration of the dispenser. 1.3. Determine the velocity of the coin when it is 2 mm below its resting position.arrow_forwardExperiment #2: Acceleration vs. Mass Link https://phet.colorado.edu/sims/html/forces-and-motion-basics/latest/forces-and-motion-basics_en.html In this lab you will determine the relationship between acceleration and mass. Choose an Applied Force at the beginning, and keep it constant for this entire experiment. Set the friction to zero. This will make your Applied Force equal to the net force. Record data for five different values of Mass. Graph Acceleration vs. Mass. Graph this in Google sheets(you want a line graph - it should only have one line). Make sure that Mass information is used as the x value Make sure that Acceleration information is used as the y value Add a trendline – see what fits best – linear, exponential, polynomial, etc … Add a copy of you graph below the table Applied Force (N) Mass (kg) Acceleration (m/s²)arrow_forwardThe following questions consider the stability of a floating iceberg. Approximate the iceberg as a perfect cylinder of uniform density, If the iceberg has a diameter of 3 meters and a length of 0.5 meters find the location of the metacenter as measured from the bottom of the iceberg. Take the density of sea water to be 1030 kg/m3 and the density of the ice to be 920 kg/m3.arrow_forward
- Find the location of the center of mass of a nonuniform rod 40cm in length if its density varies linearly from 1 g/cm at one end to 5 g/cm at the other end. Specify the center of mass location relative to the less massive end of the rod. Leave the values in g and cm. a) Find the mass of the rod in grams b) Where is the center of mass of the rod (in cm)?arrow_forwardAt what distance d, in kilometers, from the surface of the earth on a line fromcenter to center would the gravitational force of the earth on a rocket be threetimes the gravitational force of the moon on the rocket?arrow_forwardA hydraulic press is composed of two cylindrical reservoirs of R1 and R2 rays.The plungers in this press are extremely light and can move virtually frictionless and perfectly adjusted to their respective cylinders. The fluid that fills the press reservoirs is low density and can be considered incompressible. When in balance, the F2 force supported by the larger plunger is 100 times higher than the F1 force supported by the smaller one. Thus, the R2 / R1 ratio between the rays of the emboli, is worth approximately:a) 100b) 50c) 10d) 1000e) 200arrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY