WELCOME TO PHYSICS! 1) Find your name on a notecard at a seat. This is your assigned seat. 2) If you wish to be called something differently than the name.

WELCOME TO PHYSICS!1) Find your name on a notecard at a seat. This is your

assigned seat.2) If you wish to be called something differently than the

name given, write it underneath the name.3) On the back of the card, number 1 to 7 downwards and

Honestly answer the following. Only I will read these.1) List a few activities or hobbies you enjoy.2) What are your plans after high school?3) What is the one thing about yourself that you are

most proud of?4) If When you are frustrated or feeling lost in this

class, how will you resolve this?5) How do you define success in this class?6) Using 5 words or less, define your idea of physics.7) Tell me something about you that I should know as a

teacher.

What you need for class1 notebook dedicated for this class ONLY.

Calculator-Graphing is pretty much required.

(Not required but REALLY helpful)-A set of colored pens. Recommended by last few years of students.

Internet/BCPS One access

Syllabus and MoreWhat is important….

For next class…..1) Letter signed2) Questionnaire Done3) Day 1 Assignment Finished, Checked4) Day 2 video watched/checked

What will happen today?We are going to begin our study of

physics.

1) Reviewing Dimensionality2) 3 Examples done by me3) 3 Examples done by you, confirmed by

group4) 2nd Learning/Review session of units and our

first major set of definitions5) 4 Group led problems on small boards6) Our first application activity7) Summary, link to website

My Goals For TodayAt the end of today, you should have

the tools to:

1) Be able to convert between units and be able to predict functions from the units.

2) Understand the different basic units in physics and what they mean.

3) Learn the difference between position and displacement.

Lets Start…DIMENSIONAL ANALYSISWhat is it?

Converting between units through math

Strategies1) Identify what unit you are going to

change and the result unit.2) Write it out the way I will show

you3) If you have NO idea what is being

asked, it is good to try to use dimensional analysis as a start point.

Who gives a flying fig?It is really easy to screw up the

conversions OR make a wrong assumption.

Mars Climate Orbiter

Example OneLast week, my trail ride was around

16 miles per hour. How many feet per second is that?

23.4 feet per second

As your packet stated3 dimensionalities to start

Mass [M] in kg (m in equations)Length [L] in meters (d in equations)Time [T] in seconds (t in equations)

Using these to determine a general approach is a KILLER IDEA

Example TwoA car driven by a distracted panda goes from

speed vi to vf over some distance d. Which of the following represents the force of the car during that distance? (Assume force is in kg.m/s2)

A) mp (vf2 – vi

2) 2

B) mp (vf2 – vi

2) 2d

A) mp (vf – vi) 2

A) mp (vf – vi) 2d

B…this is a released question

Example 3 VOTINGYour tank holds around 18.6 gallons

of gas, but shows it to be exactly ¼ full. The next gas station is 73 miles away. You drive so your car gets 14mpg for the first ½ of that distance. What mpg do you need for the 2nd half to just make it to the gas station?

What would your plan of attack be?Find how much gas was used the first ½,

and then how much gas can be used for the 2nd ½. From that gas you can get mpg from the ½ distance.

Now its your turn…I expect you to now write down/tape

in/etc the next problems.

You will start by attempting the problem individually, then after I give the signal, discuss it with group mates and come to an agreement.

Place agreed answer kinda small on the group whiteboard.

You try 1A Jerk is defined as an acceleration in a

given time. Which of the following is the correct unit for a Jerk? Show/write your reasoning.

A) m.sB) m/sC) m/s2

D) m/s3

You Try 2A)In rotational motion, objects have

a resistance to motion called I, the moment of inertia.

A solution for it is ½ mv2 = ½ I (v2/d2)

What dimensionality is I?

[M][L2]

You Try 3 NO MATHYou are going to Paris. You have $100 to

spend today. The rate of exchange is $1.24 per Euro. It costs 4 Euro to convert the money. You want to buy a 70 Euro Panda that also has 15% sales tax. Which of these is a correct process to see if you can afford it?A) Convert $100 to Euro’s, subtract 4 Euro, compare to 70 Euro that is multiplied by .15

B) Convert $100 to Euro’s, add 4 Euro, compare to 70 Euro that is multiplied by .15

C) Subtract 4 Euro from 70 Euro that is multiplied by 1.15, convert to $, compare to $100.

D) Multiply 70 Euro by 1.15, add to 4 Euro, convert to $, compare to $100.

Now about UNITSUnit Represents

Meters: m Length, how far

Seconds: t Time, how long

Kilogram: kg Mass, how much stuff

Meter per Second: m/s Velocity, how fast

Meter per Second per Second: (m/s)/s m/s2

Acceleration, how quickly you change velocity

And prefix in unitsWe use prefix for different amounts

Prefix and symbol Relationship

Centi: c ex: cm 100 centi in a standard, 100 cents in 1 dollar

Milli: m ex: ms 1000 milli in a standard 1000 years for a millenium

Kilo: k ex: km 1000 standard in a kilo $100k is $100,000

Example: 1.2 km is how many cm?

120,000cm

On the Board 1A)Going from m/s to km/hr, will the

result increase or decrease? Explain your answer

B) Going from cm/hr to m/min, will the result increase or decrease? Explain your answer

On the Board 2Your tank holds around 18.6 gallons

of gas, but shows it to be exactly ¼ full. The next gas station is 73 miles away. You drive so your car gets 14mpg for the first ½ of that distance. What mpg do you need for the 2nd half to just make it to the gas station?

17.86mpg

On the Board…From your PacketA car on a highway is on average 4.4

meters long. It is assumed that cars go a constant 75 km per hour. Each car is expected to be 2 seconds apart. How many cars can pass a point on a highway in hour?

Hint: Determine the space needed for 1 car first.

1628 cars

ApplicationYou will start with the homework

given out right now (Dimensional Analysis)

The purpose is to give you a sense of how to analyze a situation and determine where to start.

Try the 1st 3 on a separate paper. Either individually or in groups.

1st Three…VOTINGLets see if you came up right

answers.Vote on what you got for the 1st one

A) 90 CleansB) 270 CleansC) 0 Cleans

1st Three…VOTINGLets see if you came up right

answers.Vote on what you got for the 2nd one

A) 80 ZitsB) 240 ZitsC) 0 Zits

1st Three…VOTINGLets see if you came up right

answers.Vote on what you got for the 3rd one

A) 1.77 ZitsB) 2.66 ZitsC) 0 Zits

FinallyThe QR code is linked to the wiki I

set up where there will be answers, documents, and the videos I make and reference for this class.