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 class 1 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 More What is important…. For next class….. 1) Letter signed 2) Questionnaire Done 3) Day 1 Assignment Finished, Checked 4) Day 2 video watched/checked

What will happen today? We are going to begin our study of physics. 1) Reviewing Dimensionality 2) 3 Examples done by me 3) 3 Examples done by you, confirmed by group 4) 2 nd Learning/Review session of units and our first major set of definitions 5) 4 Group led problems on small boards 6) Our first application activity 7) Summary, link to website

My Goals For Today At 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 ANALYSIS What is it? Converting between units through math Strategies 1) Identify what unit you are going to change and the result unit. 2) Write it out the way I will show you 3) 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 One Last 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 stated 3 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 Two A car driven by a distracted panda goes from speed v i to v f over some distance d. Which of the following represents the force of the car during that distance? (Assume force is in kg.m/s 2 ) A) m p (v f 2 – v i 2 ) 2 B) m p (v f 2 – v i 2 ) 2d A) m p (v f – v i ) 2 A) m p (v f – v i ) 2d B…this is a released question

Example 3 VOTING Your 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 2 nd 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 2 nd 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 1 A 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.s B) m/s C) m/s 2 D) m/s 3

You Try 2 A)In rotational motion, objects have a resistance to motion called I, the moment of inertia. A solution for it is ½ mv 2 = ½ I (v 2 /d 2 ) What dimensionality is I? [M][L 2 ]

You Try 3 NO MATH You 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 UNITS UnitRepresents Meters: mLength, how far Seconds: tTime, how long Kilogram: kgMass, how much stuff Meter per Second: m/sVelocity, how fast Meter per Second per Second: (m/s)/s m/s 2 Acceleration, how quickly you change velocity

And prefix in units We use prefix for different amounts Prefix and symbolRelationship Centi: c ex: cm100 centi in a standard, 100 cents in 1 dollar Milli: m ex: ms1000 milli in a standard 1000 years for a millenium Kilo: k ex: km1000 standard in a kilo $100k is $100,000 Example: 1.2 km is how many cm? 120,000cm

On the Board 1 A)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 2 Your 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 2 nd half to just make it to the gas station? 17.86mpg

On the Board…From your Packet A 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 cars

Application You 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 1 st 3 on a separate paper. Either individually or in groups.

1 st Three…VOTING Lets see if you came up right answers. Vote on what you got for the 1 st one A) 90 Cleans B) 270 Cleans C) 0 Cleans

1 st Three…VOTING Lets see if you came up right answers. Vote on what you got for the 2 nd one A) 80 Zits B) 240 Zits C) 0 Zits

1 st Three…VOTING Lets see if you came up right answers. Vote on what you got for the 3 rd one A) 1.77 Zits B) 2.66 Zits C) 0 Zits

Finally The 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.