Physics Chapter 2 Review & Practice

Online Resources Glencoe Physics Web Link: http://www.glencoe.com/sec/science/physics/index2.php?yr=99 Chapter 2 Links: http://www.glencoe.com/sec/science/physics/wwwlinks/index2.php?yr=99

Review Questions The meter, second and kilogram are what type of fundamental units? What system are they used in? Length, time, mass in the SI system What is a derived unit? Combinations of fundamental units How are very large and small numbers represented in science? Using scientific notation

Review Questions What is 0.0001340 in scientific notation? 1.340 x 10-4 How many significant figures are in the above number? Four What is definition of precision? The degree of exactness of a measurement or repeatability of a measurement

Review Questions When a measured value is close to the accepted value it is said to be _________? Accurate The last digit in a measurement is an ??? Estimate When multiplying numbers the result can only have as many significant figures as the? The number with the least significant figures

Review Questions Which variable manipulated or changed? The independent variable Which variable is measured or responds to the manipulated variable? The dependent variable Which axis should be used for each variable? X axis = independent, Y axis = dependent

B. Sig. figs. when multiplying or dividing: answer has the _________ number of sig. figs., in this case: ____ ____ sig. figs. 3 lower 3.73 x 5.7 = 21 2 ____ sig. figs. 2 C. Sig. figs. when adding or subtracting: 3 18.541 +106.6 125.1 ___ decimal places 1 lower answer has the _________ number of ___________________ , in this case: ____ decimal places 1

V. Converting Units: the power of "one" Ex: Convert 60 miles to kilometers. Use the conversion factor: 1 mi =__________ km This can be written as either: or Multiplying by either of these two factors does not change the ________________ (only the units) because both factors equal _______ . 1.609 1 mi 1.609 km 1.609 km 1 mi actual value one 1.609 km 1 mi Write: 60 mi x _________ = km 96.54 ~100 km

Prefixes: see PhysRT, pg. ____ at ___________ In all calculations, any prefix symbol on an SI unit must first be removed. 1 bottom Ex: d = 15 nm rewrite as: d = 15 x _____ m 10-9 SI unit prefix _________ represents ____ symbol __________ for length (meters) 10-9 with prefix without 5.3 km 1.7 cm 2.00 ms 1.21 GW 8.6 kg 5.3 x 103 m 1.7 x 10-2 m 2.00 x 10-6 s A trick b/c kg is already an SI unit 1.21 x 109 W 8.6 kg