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Semester preview Motion along a straight line Position and displacement Lecture 1: Course introduction Motion in one dimension

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Page 1: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

• Semester preview

• Motion along a straight line

• Position and displacement

Lecture 1: Course introduction

Motion in one dimension

Page 2: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

What is physics?

Most fundamental of sciences

Behavior and structure of matter

Page 3: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Galaxy NGC 300, seven million lighters away, constellation Sculptor.

Courtesy of NASA.

Page 4: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

High energy proton collision in the LHC. © CERN

Page 5: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Why study physics?

Required for major:

• Organisms and their components must obey

the underlying laws of physics

• Examples

• Physics can help explain biological processes

• Simulation: DNA molecule through cell

membrane

Find out how the world works

Because it is FUN

Demonstrations

Page 6: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Topic overview

Honda cog ad video

Fall semester 1145: Mechanics

• Motion of objects

• Forces, friction, circular motion

• Energy and momentum

• Motion of planets

• Rotational motion

• Fluids

• Oscillations and waves

Spring semester 2145: Electricity and magnetism

• Charges, circuits, magnets, light

Page 7: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Course Orientation

Course website: http://web.mst.edu/~vojtaa/phys1145/index.html

Page 8: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

A few tools:

• SI system of units (metric system): kg, m, s

• Unit conversions

• Scientific notation

• Prefixes: micro, milli, centi, kilo… (Table 1.2)

• Estimates

Please review on your own as needed.

See Ch. 1, Sec. 1.4

Page 9: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Basic math skills required in this course

• Linear equations, systems of linear equations

• Quadratic equations

• Basic trigonometry: SOHCAHTOA, Pythagoras

Trigonometry is a prerequisite for this course.If you got permission to take the course without having taken

a formal trigonometry course, make sure to review

Homework # 1 will help you review

math skills

• Vectors (will be covered next week)

Page 10: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Motion in one Dimension

Particle model or “point mass” → only translation

Things to know about a moving object:

Where is it? ➔ Position

How fast is it moving and in which direction?

➔ Velocity

How do speed and direction of motion change?

➔ Acceleration

Kinematics: Describing Motion

Page 11: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Position

• In reference to some coordinate system

• numerical value x

• x(t) is location of particle as a function of time

• Initial position: xi = x(ti) *

* Particle does not have to start at the origin

Discuss: textbook, Table 2.1, Figures 2.2 and 2.4

Page 12: Lecture 1: Course introduction Motion in one dimensionvojtaa/phys1145/handouts/Lec01_1145.pdf•Motion along a straight line •Position and displacement Lecture 1: Course introduction

Displacement

Displacement = Change in position: *

Δ𝑥 can be positive or negative ⟶ direction

If 𝑥𝑓 = 𝑥𝑖: Δ𝑥 = 0

Displacement is not the same as distance traveled!

Δ𝑥 = 𝑥𝑓 − 𝑥𝑖

* Change (upper case delta Δ) is the final

value of a quantity minus the initial value.