Conceptual Questions
1.1 The Scope and Scale of Physics
Some have described physics as a “search for simplicity.” Explain why this might be an appropriate description.
If two different theories describe experimental observations equally well, can one be said to be more valid than the other (assuming both use accepted rules of logic)?
What determines the validity of a theory?
Certain criteria must be satisfied if a measurement or observation is to be believed. Will the criteria necessarily be as strict for an expected result as for an unexpected result?
Can the validity of a model be limited or must it be universally valid? How does this compare with the required validity of a theory or a law?
1.2 Units and Standards
What are the SI base units of length, mass, and time?
What is the difference between a base unit and a derived unit? (b) What is the difference between a base quantity and a derived quantity? (c) What is the difference between a base quantity and a base unit?
For each of the following scenarios, refer to Figure 1.4 and Table 1.2 to determine which metric prefix on the meter is most appropriate for each of the following scenarios. (a) You want to tabulate the mean distance from the Sun for each planet in the solar system. (b) You want to compare the sizes of some common viruses to design a mechanical filter capable of blocking the pathogenic ones. (c) You want to list the diameters of all the elements on the periodic table. (d) You want to list the distances to all the stars that have now received any radio broadcasts sent from Earth 10 years ago.
1.6 Significant Figures
(a) What is the relationship between the precision and the uncertainty of a measurement? (b) What is the relationship between the accuracy and the discrepancy of a measurement?
1.7 Solving Problems in Physics
What information do you need to choose which equation or equations to use to solve a problem?