College Physics: A Strategic Approach Volume 1

Randall D. Knight, Brian Jones, Stuart Field

ISBN #9780321595492

2nd Edition

1,173 Questions

23,429 Students Helped

Homework Questions

Summary

Learning Objectives

Key Concepts

Example Problems

Explanations

Common Mistakes

Summary

Chapter 3 emphasizes the central nature of vectors in describing motion in two dimensions. Vectors—with both magnitude and direction—are used to analyze problems including projectile motion, motion on a ramp, relative motion between observers, and circular motion. Mastery of decomposing vectors into components, employing the tip-to-tail and parallelogram methods for addition and subtraction, and applying proper coordinate systems provides a robust framework for solving a wide variety of kinematics problems in physics.

Learning Objectives

Key Concepts

CONCEPT

DEFINITION

Definition: The practical application of Newton’s three laws to analyze and solve problems involving static equilibrium and dynamic motion.

The practical application of Newton’s three laws to analyze and solve problems involving static equilibrium and dynamic motion. •

Example Problems

Example 1

Trace the vectors in Figure $\mathrm{P} 3.1$ onto your paper. Then use graphical methods to draw the vectors (a) $\vec{A}+\vec{B}$ and (b) $\vec{A}-\vec{B}$.

Example 2

Trace the vectors in Figure $\mathrm{P} 3.2$ onto your paper. Then use graphical methods to draw the vectors (a) $\vec{A}+\vec{B}$ and (b) $\vec{A}-\vec{B}$

Example 3

A car goes around a corner in a circular arc at constant speed. Draw a motion diagram including positions, velocity vectors, and acceleration vectors.

Example 4

a. Is the object's average speed between points 1 and 2 greater than, less than, or equal to its average speed between points 0 and 1 ? Explain how you can tell. b. Find the average acceleration vector at point 1 of the three-point motion diagram in Figure $\mathrm{P} 3.4$

Example 5

Figure 3.11 showed the motion diagram for Anne as she rode a Ferris wheel that was turning at a constant speed. The inset to the figure showed how to find the acceleration vector at the lowest point in her motion. Use a similar analysis to find Anne's acceleration vector at the 12 o'clock, 4 o'clock, and 8 o'clock positions of the motion diagram. Use a ruler so that your analysis is accurate.