## 6.24 | solutions for openstax™ “college physics”

To others, textbooks conjure up images of the heaving load of knowledge we have to lug around school five days a week. More illustrations, diagrams, maps, and special features tend to motivate interest in the subject matter, particularly in science textbooks, so the size of textbooks is increasing. Older science textbooks are heavily packed with text, equations, and problems, while newer textbooks feature plenty of white space, lab experiments, and “society relations” sections in the book, among other items. The newer books are certainly more engaging for students because they have fascinating illustrations that help students imagine complex topics, minimize monotony, and are easier to skip around in. For the sake of durability, most school textbooks are hardcover. The weight of a hardcover book ranges from two to seven pounds (0.9 kg to 3.18 kg).
The words “weight” and “mass” are not synonymous. Weight is the force of gravity on an object, and mass is resistance to acceleration. Mass is often known as the measure of how much matter an object contains. For the most part, an object’s weight is equal to its mass. That is, a larger (mass) object will weigh more than a smaller object (with less mass). The kilogram (kg) is one unit of mass, while newtons is one unit of weight (lbs). On Earth, one kilogram weighs 9.8 N, or around 2.2 pounds.

## Physics 111 : hw 6 – problem 12

(f) Sound travels at a fraction of the speed of light.

### Your textbooks are wrong, this is what cells actually look

VIEW SOLUTIONQ 5 | Page 35In order for the speed of light in vacuum to be unity, a new unit of length is chosen. What is the current unit’s equivalent of the distance between the Sun and the Earth if light takes 8 minutes and 20 seconds to travel the distance? SOLUTIONQ 6 | PAGE 35 VIEW SOLUTIONQ 6 | PAGE 35 VIEW SOLUTIONQ 6 Which of the following devices is the most accurate at measuring length:
(c) an optical device capable of measuring length to a wavelength of light?
VIEW SOLUTIONQ 7 | Page 35A student uses a microscope with a magnification of 100 to determine the thickness of a human hair. He makes 20 observations and discovers that the average hair width in the microscope’s field of view is 3.5 mm. What do you think the hair thickness is? SOLUTIONQ 8.1 | Page 35 VIEW SOLUTIONQ 8.1 | Page 35 VIEW SOLUTIONQ 8.1 | Please respond to the following questions:
A screw gauge has a circular scale of 200 divisions and a pitch of 1.0 mm. Do you believe that increasing the number of divisions on the circular scale will arbitrarily increase the screw gauge’s accuracy? ANSWER THE FOLLOWING: VIEW SOLUTIONQ 8.3 | Page 35

### Note: there is a mistake at 1:53:43. to go from c to k, you

The column “Subtask” refers to the Appendix subtasks. The columns “AT” (Algebraic Technique) and “Trigger,” with the exception of the columns “Time,” “Subtask,” and “ad hoc strategies,” contained drop-down boxes with various choices. One of the choices in the third column “AT” of the spreadsheet was chosen (coded) based on the algebraic technique used during a procedure: “multiplication of both sides,” “division of both sides,” “substitution,” “taking the square root of both sides,” “squaring both sides,” and “subtraction from both sides.” If she used ad hoc strategies instead of the latter, the specifics were detailed in the column “ad hoc strategies.”
The choices for the last column, “Trigger,” are “positive,” “bad,” or “missed opportunity.” When she selected the correct procedure and executed it correctly with a score of “1,” or incorrectly with a score of “0.5,” the procedure was coded “positive” or “negative.” The third case, in which the neutral student made no effort to solve the task, such as when she skipped a necessary technique or used ad hoc approaches, is referred to as a “missed opportunity.” SSB ( percent ) is the symbol sense activity percentage per subtask as a result of this. OSSB ( percent ), which is the overall symbol sense activity percentage for the entire set of subtasks, and OBAS ( percent ), which is the overall BAS percentage for the entire set of subtasks, are two other ratings. ( fracmathrmsummathrmofmathrmallmathrmsubmathrmtaskmathrmscores25bullet 100 percent ) and ( fracmathrmsummathrmofmathrmallmathrmsubmathrmtaskmathrmscoresmathrmrequiringmathrmBAS The number “25” in OSSB ( percent ) is the total of 20 procedures involving LS and PS, and five procedures involving BAS, as shown in the Appendix solution set. A perfect performance of each procedure results in a maximum score of 25.

### 1.32 | solutions for openstax™ “college physics”

Physicists, other scientists, and engineers are often required to make approximations or “guesstimates” for a given quantity. What is the distance between two points? What is a given item’s estimated density? In a circuit, how much of a current will there be? Many approximations are based on formulae where the input quantities are only understood to a small degree of accuracy. You can learn approximation skills as you develop problem-solving skills (which can be extended to a variety of fields through a study of physics). These abilities can be developed by thinking quantitatively and being able to take risks. Experience, as well as familiarity with units, are beneficial in every endeavor. We may rule out certain possibilities or numbers with these approximations. Approximations also encourage us to challenge others and direct us in our scientific approaches. To demonstrate this principle, let’s look at two instances.
Can you provide an estimate of the height of a building on your campus or in your neighborhood? Let us make an educated guess based on a person’s height. We will measure the height of a 39-story building in this example.