IB1 Chapter 2 Noteguides (1)

IB Physics Linear Kinematics (Chapter 2) Syllabus Text: Physics 6 th edition by Douglas Giancoli Block In Class Due on this class 1 Sept 4/5 -Hand out Syllabus/Course Policy -Speed Trap lab outside DI -Calculating Speed/Sig Figs -Information card -Video Flip 1B-1E/Noteguide Bring a calculator, a writing utensil, and paper Turn in: Completed information card 2 Sept 6/9 -Seating in Quad Pods -Speed Trap Example GW -Uncertainty worksheet, Speed Trap Lab, FA 1.1 Video - Tour of the website (I will email you a link) VF: 1A Sig Figs (optional) VF: 1B-1E Uncertainty Practice: Uncertainty Worksheet 3 Sept 10/11 SA 1.1 Uncertainty (first 30 minutes) VF -2C-Acceleration DI -Vector Nature of Velocity Turn in: FA 1.1 4 Sept 12/13 DI -Example Kinematics GW -Solving Kinematics Problems P2.3 GW -FA 2.3 - suvat flashcards/Data Packets/names on calculators! VF: 2C, 2D Kinematics Practice: Practice for 2.3 5 Sept 16/17 DI -Demos for Free Fall GW -Solving Free Fall problems Lab -Get tapes for Moving Plots DI -How to analyze your tapes VF: 2H Free Fall Problems Practice: Practice for 2.3 6 Sept 18/19 SA 2.3-Kinematics (first 30 minutes) VF -2F-Displacement Graphs DI -Tangent Lines for slopes Turn in: FA 2.3 Practice: Practice for 2.3 7 Sept 20/23 GW -Work on Graphs of motion -Demo of Plot Matching lab VF: 2G Velocity Graphs Practice: Practice for 2.4 8 Sept 24/25 Lab -Air Rocket data gathering GW -Labs Practice: Practice for 2.4 9 Sept 26/27 SA 2.4-Free Fall (first 30 minutes) GW -Labs Turn in: FA 2.4 1 Sept 30/ Oct 1 DI -Vector Components GW -Labs or VF 2 Oct 2/3 More on Vectors! VF: 3C, 3D, 3E Turn in: Moving Plots lab Turn in: Air Rocket lab Assignments  4 Labs: o Speed Trap Lab – done the first day of class, written up the second day. No handout o Air Rocket Lab-outdoors o Moving Plots Lab – tape timer dots thingy o Plot Matching Lab – matching the plots on the computer/written note saying you did it. No handout  3 Formative/Summative Assessments: o 1.1 Propagation of Uncertainty o 2.3 Basic Kinematics o 2.4 Free Fall Kinematics Handouts

Significant Figures (sig figs) 1. The leftmost nonzero digit is the most significant digit 2. If there is no decimal point, the rightmost nonzero digit is the least significant digit 3. If there is a decimal point, the rightmost digit is the least significant digit even if it is a zero . 4. All digits between the least and most are also significant. 3010 3010.00 20 20. 20.0 30.010 3.200x10 4 100 1.0x10 2 100. 0.012 0.000150 37 people in a class 50,000 at a rally In college you will learn some rules about propagating sig figs when you do calculations, but for now let's round our answers to the operand with the fewest sig figs.

Answers: 57 ± 5, 7.6 ± 0.9, 4 ± 5

1D - Multiplying or dividing the rule is: With percents: (first video) (5 ± 10%) x (20 ± 15%) With absolute uncertainty: (second video) (Write the weird math expression here) Example: A metal plate measures 21.1 + 0.5 cm by 15.3 + 0.1 cm. What is its area? Step 1 - Step 2 - Try these examples: (Again - solved on the website) (45 ± 1) x (12 ± 1) = ?? 540. ± 57 (30.0 ± .7) / (1.2 ± .1) = ?? 25 ± 2.7 1E - The rule for powers: (Write the math expression here) Example: A cube measures 2.52 ± 0.05 cm on a side. What is its volume in cc? Step 1 - Step 2 - Try these examples: (4.5 ± 1.0) 2 = ?? 20.3  9.0 √ 25.0 ± 0.2

Uncertainty – Any measurement or value in Physics will have an uncertainty. Here’s how to estimate that uncertainty:  Measuring with a ruler: The uncertainty is ± half the smallest division on the ruler. If you measure something that is 12.4 cm long with a ruler that has mm divisions, then your uncertainty is ± .5 mm or ± .05 cm so you would say 12.4 ± .05 cm  Using a digital readout: The uncertainty is ± the last digit. If you have an ammeter that reads 1.56 Amps, it would be 1.56 ± .01 Amps.  Multiple trials of something with random error: You could say that it is the average, ± range/2. If you did 3 trials for the rocket lab, and a rocket stayed up in the air for 5.23, 5.25, 5.12, and 5.36 seconds, you could say that it is 5.24 (the average) ± 0.12 (the range/2, i.e. (5.36-5.12)/2). Directions : The answers are on the side. (Uncertainties should be rounded to 1 or 2 sig figs, and the number of decimal places in the answer should not exceed the limit of the uncertainty) Adding or subtracting – the uncertainty of a sum or difference is the sum of the uncertainties 25.2 ± 0.7 13.1 ± 0.2 23.12 ± 0.01 24 ± 2 21.3 ± 0.5 6.87 ± 0.03 + 12.1 ± 0.5 - 16.25 ± 0.02 + 127 ± 5 - 21.1 ± 0.1 151 ± 7 0.2 ± .6?? Multiplying and/or dividing – if y = ab/c, then  y/y =  a/a +  b/b +  c/c (  reads uncertainty of) Round uncertainty to two sig figs. 31.6 ± 3.8 5.10 ± 0.2 3.12 ± 0.05 484 ± 2 137 ± 9 3.59 ± 0.15 x 6.20 ± 0.5 x 1.15 ± 0.03  12.0 ± 1  1.78 ± 0.05 40.3 ± 3.5 77.0 ± 7.2 (These are easy - % uncertainties are fractional uncertainties, so just add the %) 12% 0. What is the percent uncertainty of the area of a rectangle if the length is uncertain by 5%, and the width by 7% 9% 1. What is the percent uncertainty of the volume of a cube if the sides each have a percent uncertainty of 3%? 15% 2. A sphere has a radius with an uncertainty of 5%, what is the percent uncertainty of the volume? Powers – if y = a n , then  y/y = |n  a/a| (  reads uncertainty of) Round uncertainty to two sig figs. (12.6 ± 1.2) 2 (3.4 ± .1) 3 √(16 ± 3) 3 √(343 ± 31) 159 ± 30. 39.3 ± 3.5 4.00 ± .38? 7.00 ± 0.21 Word problems (the test isn't like these : - ) 21.2 ± 1.3 m/s 0. A car goes 45 ± .5 m in 2.12 ± 0.11 seconds. What is the speed of the car, and what is the uncertainty of the speed? 14.7 ± .8 m 2 .77? 1. What is the area (with uncertainty) in square meters of a rectangular room that measures 3.5 x 4.2 m where both measurements have an uncertainty of .1 m? 140.4 ± 6.0 cm 2. A staircase has 12 steps, each one being 11.7 ± .5 cm high. What is the total height of the staircase with uncertainty? (Add twelve together…) 1.2 ± 1.3 cm Yes 3. One board is 24.1 ± .5 cm long, and another is 25.3 ± .8 cm long. How much longer is the second than the first? Could the first possibly be longer? 452.4 ± 7.5 cm 2 4. What is the area (with uncertainty) of a circle that is 12.0 cm ± .1 cm in radius? (area =  r 2 so that is  x r x r) 589 ± 68 cc 5. A sphere has a radius of 5.2 ± .2 cm. What is its volume in cubic centimeters? (V = 4/3  r 3 )

2C - Velocity and acceleration (the second video - Velocity and Acceleration) Consider the last example problem: What is your final velocity if you are going 12 m/s and you accelerate at 0.48 m/s/s for the next 16 seconds? New Formula: v = u + at Write down what these are: v = u = a = t = Try these examples: 1. A car going 24.8 m/s decelerates at - 2.451 m/s/s for 1.67 s. What is its final velocity? (20.7 m/s) 2. What is the acceleration of a ball that goes from 12.5 m/s to 17.8 m/s in 2.5 seconds? (2.1 m/s/s) 3. A cop clocks a car going 22.4 m/s after having accelerated at -7.45 m/s/s for the last 3.4 seconds. What was the initial velocity of the car? (48 m/s) 4. What time will it take a train to slow from 23.2 m/s to 14.8 m/s if the acceleration is -1.2 m/s/s? (7.0 s) In the unused space below, draw a cartoon of Principal Dellerba chasing Spaceman Spiff through an asteroid belt:

Try these example problems. 1. A cart stops in a distance of 3.81 m in a time of 4.51 s. What was its initial velocity? (1.69 m/s) 2. A car going 12 m/s accelerates at 1.2 m/s/s for 5.0 seconds. What is its displacement during this time? (75 m) 3. Another car with a velocity of 27 m/s stops in a distance of 36.74 m. What was its acceleration? (-9.9 m/s/s) 4. A car’s brakes slow it at 9.5 m/s/s. If it stops in 47.3 m, how fast was it going to start with? (30. m/s) 5. What time will it take a car going 23 m/s to start with, and accelerating at 3.5 m/s/s, to go 450 m? (10.7585 ≈ 11 s Hint - it is quadratic with "No v" but you can use "No t" to find v, and then use "No s" to find t without using the quadratic equation)

Practice for 2.3 On a separate sheet of paper, show your work. List your knowns (suvat), show which formula you are going to use, and show the knowns in that formula. Regular one step or two step problems: 11.2 m 1. A Pirate Ship accelerates uniformly from 1.80 m/s to 5.60 m/s with an acceleration of 1.25 m/s/s. What was its displacement? 8.28 m/s 2. A lemur going 3.45 m/s accelerates at 1.52 m/s/s for 3.18 s. What is its final velocity? -8.85 m/s/s 3. A giant lizard stops in 5.85 m in 1.15 s. What was its acceleration? 12.4 s 4. A tuna going 2.35 m/s accelerates at 0.208 m/s/s covering a distance of 45.0 m. What time did it take? 7.27 m 5. A lemming speeds up from rest to 5.19 m/s in 2.80 s. What is its displacement during this time? 21.6 m/s 6. An accident scene detective knows that a car with a deceleration of -7.14 m/s/s was brought to rest in 32.8 m. What was the initial velocity? -1.22 m/s/s 7. What is the acceleration of an ATV that goes from 12.0 m/s to 7.50 m/s in 3.68 s? 41.9 m 8. A XC runner accelerates uniformly for 8.20 s at 0.540 m/s/s having a final velocity of 7.32 m/s. What is their displacement during this time? 22.8 m/s 9. A racecar accelerates at 5.13 m/s/s for 3.35 s covering a distance of 105 m. What was its initial velocity? 21.9 m/s 10. A car avoiding an accident is brought to rest over a distance of 56.0 m in 5.12 s. What was its initial velocity? -4690 m/s/s 11. A baseball going 38.0 m/s decelerates to rest over a distance of 0.154 m. What was its deceleration? (It's big) -2.01 m/s/s 12. A car goes from 27.2 m/s to 14.7 m/s in 6.23 s. What is its acceleration? 458 m 13. A train going 45.0 m/s decelerates at -2.17 m/s/s for 17.9 s. What is its displacement during this time? 4.36 m/s 14. A hamster going 2.7 m/s accelerates uniformly for 6.52 s, covering a distance of 23.0 m. What was its final velocity? (it's riding a hamster scooter) 2.33 s 15. A car is going 15.0 m/s after having decelerated at -6.25 m/s/s over a distance of 52.0 m. What time did it take? -25.1 m/s 16. A hot pocket accelerating at -9.81 m/s/s from rest falls downward -32.1 m. What is the final velocity? 18.2 m/s 17. A car accelerates uniformly for 8.70 s with a final velocity of 31.5 m/s over a distance of 216 m. What was its initial velocity? 2.39 s 18. A car that can brake at -8.92 m/s/s will take what time to decelerate from 33.1 m/s to 11.8 m/s? 81.6 m 19. A rollercoaster car going 8.60 m/s decelerates at -0.215 m/s/s for 11.0 s. What was its displacement during this time? 47.1 s 20. A space probe is going 615 m/s after having decelerated at -0.147 m/s/s over a distance of 29,100 m. What time did it take? Two-part kinematics problems: 39.2 m 21. A dragon accelerates from 1.13 m/s to 3.60 m/s in 4.13 seconds. Over what distance could it accelerate from rest to 6.85 m/s if it had the same acceleration? 4.98 s 22. A car accelerates uniformly from rest, covering 65.0 m in 5.62 seconds. What time would it take the same car to go from 8.90 m/s to 29.4 m/s if it had the same acceleration? 7.73 m/s 23. A runner covers 21.5 m accelerating uniformly from rest to 9.94 m/s. What was their speed when they had covered only 13.0 m? 2.84 s 24. A train decelerates from 35.0 m/s to 22.0 m/s in 42.0 seconds. What time did it take it to cover 98.0 meters from the beginning? 17.5 s 25. A car accelerates from rest to 23.0 m/s over a distance of 231 m. What time would it take it to accelerate from rest to 20.0 m/s if it accelerated at the same rate?

Noteguide for Displacement Graphs - Videos 2F Name Slope on a position time graph: Whiteboards: Keep in mind that when you find the slope, you should use the entire line segment. (i.e. 2.0 seconds, use the entire line from t = 0 to t = 3.0 s, and find the rise/run for that entire segment.) 1. What is the velocity at 2.0 s? (0.67 m/s) 2. What is the velocity at 4.0 s? (0 m/s) Position in meters T i m e i n s e c o n d s 5 s 4 m

3. What is the velocity at 6.2 s? (2.0 m/s) 4. What is the velocity at 8.15 s? (-3.0 m/s)

Noteguide for Velocity Graphs - Videos 2G Name Slope of velocity graphs: What does the slope on a velocity graph mean? Whiteboards: Keep in mind that when you find the slope, you should use the entire line segment. 1. What is the Acceleration at 1.15887 seconds? (1.5 m/s/s) 2. What is the Acceleration at 8.1 s? (-0.50 m/s/s) (In calculus the slope is the derivative)

Area under velocity graphs: What does the area under a velocity graph mean? Whiteboards: "Area under" means the area between the graph and the x-axis. The units of this "area" are meters in this case, so it's not area in a strict sense. Graph areas can have all kinds of different units. 1. What displacement between 2 and 4 seconds? (6.0 m) 2. What displacement between 4 and 7 seconds? (13.5 m) (In calculus the area under is the integral)