PHYS 101 Kinematics Lecture Notes

Course Details

PHYS 101 taught by Qingze Guan;

• Email: qingze.guan@wsu.edu

• Office Hours: Fridays 4-5 PM or by appointment (Webster 947G)

Course Overview

• Units of Study:

  • Kinematics (Target Points: 103)

  • Forces (Target Points: 109)

  • Energy (Target Points: 128)

  • Waves (Target Points: 82)

• Grading:

  • Average of each unit grade; no curve applied.

  • Calculate final grades using provided Excel calculator, as Canvas may show incorrect percentages.

How to Succeed in PHYS 101

• Physics is primarily about problem-solving; minimal memorization required.

• Build quantitative analytical skills through consistent practice.

• Keep up with readings on Perusall to prepare for classes, which enhances participation.

• Engage in every class session and utilize iClicker for participation points.

• Participate in weekly in-class tutorials with learning assistants for additional support.

• Complete weekly homework problems by deadlines.

• Take advantage of extra credit opportunities within each unit (e.g., targeted 103 pts but maximum of 138 for Kinematics Unit).

Reading Assignments and Participation

• Perusall: Required reading to be completed 1 hour before class. Aim to engage deeply with the text by posing questions and participating in discussions.

  • Assignments graded based on best 5 contributions.

• iClicker: Register for free, answer questions during lectures for 1 point for participation and additional points for correct answers.

Fundamental Concepts in Physics

• Physics Definitions:

  • Classical Physics: Describes motion in conditions typical in daily life, focusing on speeds significantly lower than light speed, with larger observable objects.

  • Modern Physics: Deals with phenomena at relativistic speeds or where quantum effects are significant, as articulated by theories such as relativity and quantum mechanics.

• Quantities and Units:

  • Fundamental quantities include Length (meters), Mass (kilograms), and Time (seconds).

  • Derived quantities like Speed can be calculated using the formula:
    Speed = \frac{Length}{Time}

Measurement and Unit Conversion

• Metric Prefixes: Important for expressing different magnitudes in SI units.

  • For example, converting grams to kilograms:
    30\text{g} \times \frac{1\text{kg}}{1000\text{g}} = 0.030\text{kg}

Kinematics: The Study of Motion

• Kinematics focuses on describing motion without considering forces.

• Key Terms:

  • Displacement: Change in position, given by the equation
    \Delta x = xf - xi

  • Distance: The total path length traveled, independent of direction.

  • Understanding the difference in magnitude and direction between distance and displacement is crucial.

Graphical Representation and Physics Diagrams

• Motion Diagrams: Visual representation highlighting the position of an object at different times, allowing you to analyze motion quantitatively.

• Velocity: Defined as displacement over time. For average velocity, use:
  \vec{v}_{avg} = \frac{\Delta x}{\Delta t}

Learning and Homework Strategies

• Attend Learning Group Activities (LGAs) where you collaborate on group worksheets designed to reinforce your understanding of the material.

• Utilize Homework practice that involves both multiple-choice questions and numerical problems with set deadlines.

Kinematics focuses on describing motion without considering forces. Here are some key equations relevant to kinematics:

1. Displacement: The change in position of an object is given by the equation
   \Delta x = xf - xi
   where

   • $x_f$ is the final position, and

   • $x_i$ is the initial position.

2. Average Velocity: Defined as displacement over time, calculated as follows:
   \vec{v}_{avg} = \frac{\Delta x}{\Delta t}
   where

   • $\Delta t$ is the change in time.

3. Average Speed: The total distance divided by the total time taken.

4. For uniformly accelerated motion, the following equations can be used:

   • Final Velocity: vf = vi + at where

     • $v_f$ is the final velocity,

     • $v_i$ is the initial velocity,

     • $a$ is the acceleration, and

     • $t$ is the time.

   • Displacement with constant acceleration:
     \Delta x = v_i t + \frac{1}{2} a t^2

   • Final velocity squared:
     vf^2 = vi^2 + 2a\Delta x

Understanding these equations is crucial for analyzing motion within the study of kinematics.