#### Transcript PHYSICS I UNIT 1 - science-b

PHYSICS I UNIT 1 Motion Kinematics One – Dimensional Motion JAVA APPLETS http://www.walter-fendt.de/ph14e/ WILEY APPLETS http://higheredbcs.wiley.com/legacy/college/halliday/0 471320005/simulations6e/index.htm?newwindow=true Lesson One Motion chap 2 UNIT 1 Lesson 1 Objectives Position vs. Time Do Now! Graphs Men’s USA runner Maurice Using Data Greene won the gold in the 100 meter sprint with a time of 9.87 s. Calculate: What was his average velocity? Honor: If his initial velocity was 0, what was his average acceleration? Homework Problems pg 52 #’s 43 – 50 ALL Problems pg 52 #’s 51 – 61 ODD Using Average Velocities Average Accelerations UNIT 1 Lesson 1 Definition of Speed Speed is the distance traveled per unit of time (a scalar quantity). d = 20 m A Time t = 4 s B vs = d t = 20 m 4s vs = 5 m/s Not direction dependent! UNIT 1 Lesson 1 Definition of Velocity Velocity is the displacement per unit of time. (A vector quantity.) s = 20 m Δx=12 m A 20o Time t = 4 s B = 3 m/s at 200 N of E Direction required! UNIT 1 Lesson 1 Lesson #1 In Class Equations of one- dimensional motion page 51 Answer Review Concepts page 39 practice problems #’s 9 – 13 PRACTICE / DEMO Cart Rolling down Ramp Measure Displacement Measure Time Calculate Average Velocity Position vs. Time http://webphysics.davidson.edu/physlet_resources/physlet_ph ysics/contents/mechanics/one_d_kinematics/default.html Constant Acceleration vs. Time http://webphysics.davidson.edu/physlet_r esources/physlet_physics/contents/mecha nics/one_d_kinematics/default.html The BIG 5 UNIT 1 Lesson 2 Chap 3 Objectives Do Now! Navy jets launch from aircraft carriers using catapults go from 0 to launch speed in 175 feet (5.334X 101 m) in 2.15 sec. What is the average velocity as it travels down the catapult? How far has it traveled at 1.10 seconds? Homework Summary Sheet chap 3 terms, Solving for -Average Velocity -Acceleration, Final Velocity Page 61 & 64 Practice Problems 1 – 10 ALL Utilize THE BIG FIVE EQUATIONS!!! Equations on Page 79 (Chapter 3) Each student should be able to solve for : Vf when Vi, ,a and t are known Vi when, Vf ,a and d are known d when Vf , Vi and t are known d when a , Vi and t are known a when d , Vi , Vf and t are known UNIT 1 Lesson 2 Vf2 = V02 + 2aΔd E.g. A train accelerates from 10 m/s to 40 m/s at an acceleration of 1m/s 2. what distance does it cover during this time. Using V2 = V02 + 2aΔs, we sub in values 40 for V, 10 for V0 and 1 for a. Re-arranging to solve for s, we get: ΔS = 750 m With Significant Digits ΔS = 800 m UNIT 1 Lesson 2 d = V0Δt + 0.5 a Δt2 E.g. A body starts from rest at a uniform acceleration of 3 m/s2. how long does it take to cover a distance of 100m. Using d = V0Δt + 0.5 a Δt2, we sub in values 3 for a, 0 for V0 and 100 for s. Re-arranging the equation and solving for t (using the quadratic formula), we get: t = 8.51 or -8.51 seconds. As time cannot be negative, t = 8.51 seconds. t = 9 seconds UNIT 1 Lesson 2 d = Vavg * t = (V0 + Vf)/2 × t A car decelerates from 20.0 m/s to 10.0 m/s over a period of 10.0 seconds. How far does it travel during this time period. Using d = (V0 + Vf)/2 × t, we sub in values 20.0 for V0, 10.0 for Vf and 10.0 for t. Solving for s, we get: d = 150m Note: UNIT 1 Lesson 2 All units must be converted such that they are uniform for different variable throughout the calculations. Time seconds Distance meters Velocity m/s Acceleration m/s2 Kinematic quantities (except time) are VECTORS and can be negative. UNIT 1 Lesson 2 In Class Pages 60 – 63 Examples 1 and 2 PRACTICE / DEMO Motion with Constant Acceleration HOMEWORK Summary Sheet chap 3 terms, Solving for -Average Velocity -Acceleration, Final Velocity Page 61 & 64 Practice Problems 1 – 10 ALL REVIEW LAB I {F-150} Work Sheet http://www.walterfendt.de/ph14e/acceleration.htm Data Tables and Graphs UNIT 1 Lesson 3 Objectives Calculate: Average Velocities from data tables (and graphs) Do Now! What is the average acceleration of the A-6 Intruder as it travels down the catapult from 0 to 150 Knots (7.62 X 101 m/s) in 2.15 seconds? Calculate: Average Accelerations from data tables (and graphs) Homework Pg: 65 - 71 Practice Problems #19, 22, 25, 27 32 #41 UNIT 1 Lesson 3 Position vs. time graph (velocity) 9 8 p o s i t i o n No Motion (zero velocity) 7 6 5 Uniform Motion (constant velocity) 4 3 Accelerated Motion (Increasing/chan ging velocity) 2 1 0 x, (m) 1 2 3 time, t (s) 4 UNIT 1 Lesson 3 velocity vs. time graph (acceleration) 9 8 v e l o c i t y 7 Uniform Motion (zero Acceleation) 6 5 Uniform Acceleration (constant acceleration) 4 3 Decreasing Acceleration 2 v, 1 (m/s) 0 1 2 3 time, t (s) 4 UNIT 1 Lesson 3 Graphical Analysis vavg Instantaneous Velocity: Dx x2 x1 Dt t2 t1 x2 Dx x1 Dt t1 t2 vinst Displacement, x Average Velocity: Dx (Dt 0) Dt slope Dx Dt Time UNIT 1 Lesson 3 Uniform Acceleration in One Dimension: Motion is along a straight line (horizontal, vertical or slanted). Changes in motion result from a CONSTANT force producing uniform acceleration. The velocity of an object is changing by a constant amount in a given time interval. The moving object is treated as though it were a point particle. Example 6: An airplane flying initially at 400 ft/s lands on a carrier deck and stops in a distance of 300 ft. What is the acceleration? vo = 400 ft/s vf = 0 + Step 1. Draw and label sketch. Step 2. Indicate + direction Example: (Cont.) vo = 400 ft/s vf = 0 + Step 3. List given; find information with signs. Given: vo = 400 ft/s v=0 - initial velocity of airplane - final velocity after traveling Δx = +300 ft Find: a = ? - acceleration of airplane Given: vo = +400 ft/s v=0 Δx = +300 ft Step 4. Select equation that contains a and not t. 0 vf2 - vo2 = 2aΔx a= Why is the acceleration negative? -vo2 2x = -(400 ft/s)2 2(300 ft) a = - 300 ft/s2 Because Force is in a negative direction which means that the airplane slows down Lesson # Velocity LAB UNIT 1 Lesson 4 Objectives Measuring times of roll Calculate THE ACCELERATION THE VELOCITIES OF AN F-150 ROLLING DOWN THE ACADEMIC WING HILL. Homework Complete LAB 1 BRING LAPTOP with “EXCEL” for next class UNIT 1 LESSON 5 Lab Review - Excel Do Now! By Team swap labs Check Data and Calculations Read Results and Conclusion sections Objectives Utilizing Excel Plot Data and obtain Graphs of: Evaluate Effort using EEMO ..\..\Physics I LABs\Motion\CarA vs Car B Graphs and data tables.xls Position vs. Time Velocity vs. time Acceleration vs. time Homework On Excel create a graph that shows a Lacrosse ball falling at a constant acceleration of 9.8 m/s2 for 30 seconds. Aaaaaaaah! Free Fall Do Now! A lacrosse ball is dropped and falls from the BIW Crane. If the Cranes is 350.0 ft tall (107.7 meters). How long will it take the ball to hit the ground? What will the velocity be? Homework Page 74 Practice Problems #’s 42 – 46 Section Review #’s 47 Page 82 #’s 97, 100, 101 UNIT 1 Lesson 6 Objectives Be able to utilize the BIG 5 Equations to calculate: Velocity Displacement of a falling {NO Friction} object on Earth Sign Convention: A Ball Thrown Vertically Upward avy== =-0 + avy= ==-++ ya =+-v == • Displacement is positive (+) or negative (-) based on LOCATION. UP = + Release Point vya== =-0- • yv= = -Negative Negative a=- Velocity is positive (+) or negative (-) based on direction of motion. • Acceleration is (+) or (-) based on direction of force (weight). UNIT 1 Lesson 6 PRACTICE / DEMO In Class Page 74 Practice Problems #’s 42 – 46 Section Review #’s 47 Page 82 #’s 97, 100, 101 Free Fall http://higheredbcs.wiley.com/legacy/ college/halliday/0471320005/simulatio ns6e/index.htm?newwindow=true Free Fall- 2 http://www.walterfendt.de/ph14e/accelera tion.htm LAB 2 Calculate Gravitational - Acceleration in BATH, ME UNIT 1 Lesson 7 Objectives Be able to utilize the BIG 5 Equations to calculate: Velocity Displacement Acceleration of a moving object Do Now! 2 minutes A lacrosse ball is dropped and falls from the BIW Crane. If the Cranes is 350.0 ft tall (107.7 meters). How long will it take the ball to hit the ground? What will the velocity be? Homework Finish LAB REPORT Typed UNIT 1 Lesson 8 You must know how to do these actions: Calculate Average Velocities from data Calculate Average Accelerations from data Calculate times and distances given Average Velocities & Accelerations Calculate Average Velocities & Accelerations given times and distances Calculate and / or measure Average Velocities from data tables (and graphs) Calculate and / or measure Average Accelerations from data tables (and graphs) Calculate Acceleration due to gravity of an object in free fall Calculate an objects velocity in free fall Constant Acceleration Motion DO NOW: What is the gravitational Acceleration in Bath, ME? Would it be larger or smaller on Mount Everest? Why? UNIT 1 Lesson 8 In Class / Homework: Page 82 – 83 #’s 103, 107, 108, 109, 110, 111, 11, 113 REVIEW Test Lesson 10 LESSON 9 Review PHYSICS I UNIT 1 MOTION Do NOW: TEST Homework: Chapter 4 What are Newton’s THREE Law’s Give and example when it they happened to YOU!