First jet powered man to cross English channel Sept 26, 2008 Position vs Time Graphs Examine the data table of a plane in flight shown below:plane Time.

Slides:



Advertisements
Similar presentations
Kinematics: What is velocity and acceleration?
Advertisements

Kinematics Notes Motion in 1 Dimension Physics C 1-D Motion
Graphing motion. Displacement vs. time Displacement (m) time(s) Describe the motion of the object represented by this graph This object is at rest 2m.
Linear Motion III Acceleration, Velocity vs. Time Graphs.
Kinematics Acceleration 1 Motion with Constant Acceleration Instantaneous Acceleration Acceleration.
How do we describe motion?
Constant Velocity and Uniform Acceleration Teacher Excellence Workshop June 18, 2008.
Practicing with Graphs
Motion with Constant Acceleration
Montwood High School Physics R. Casao
Learning Goals Draw displacement-time graphs, and use the graphs to calculate average velocity and instantaneous velocity of moving objects in one dimension.
Motion Graphing Position vs. Time Graphs
Physics Montwood High School R. Casao
Welcome to Physics C  Welcome to your first year as a “grown-up” (nearly!)  What are college physics classes like?  Homework for the AP student  Keeping.
Ch 2 Velocity ~Motion in One Dimension~. Scalar versus Vector Scalar – quantity that only has magnitude Vector – quantity that has magnitude and direction.
What is the rate change in position called?
Acceleration (a vector quantity) is defined as the rate of change of velocity. It has units of m/s 2 Acceleration can be positive, negative, or zero. An.
Unit B 1.3 Acceleration.
Acceleration Chapter 2 Section 2.
Acceleration 1D motion with Constant Acceleration Free Fall Lecture 04 (Chap. 2, Sec ) General Physics (PHYS101) Sections 30 and 33 are canceled.
You need: Binder For Notes.  Describe motion in terms of frame of reference, displacement, time interval and velocity.  Calculate displacement, average.
Kinematics in One Dimension. Mechanics Kinematics (Chapter 2 and 3) The movement of an object itself Concepts needed to describe motion without reference.
Linear Kinematics : Velocity & Acceleration. Speed Displacement - the change in position in a particular direction and is always a straight line segment.
Honors Physics Chapter 3
Ch 2 Velocity ~Motion in One Dimension~. Scalar versus Vector Scalar – quantity that only has magnitude –In the previous slide, which is the scalar? Vector.
Motion in 1D. Forces  Remember that an imbalance in forces results in an acceleration  If all forces are balanced we get a constant velocity  Because.
Acceleration and non-uniform motion.
Accelerated Motion Merrill Physics Principles and Problems.
Lesson Average Speed, Velocity, Acceleration. Average Speed and Average Velocity Average speed describes how fast a particle is moving. It is calculated.
Acceleration- Change in Velocity
24 h of air traffic 1. Position vs Time Graphs Examine the data table of a plane in flight shown below:plane Time (s)Position (m)
Mathematical Model of Motion Chapter 5. Velocity Equations Average velocity: v =  d/  t To find the distance traveled with constant or average velocity.
Graphing Activity Describing the motion of an object is occasionally hard to do with words. Sometimes graphs help make motion easier to picture, and therefore.
Which line represents the greater speed? Graphing motion The greater the speed, the steeper the slope.
Velocity Acceleration AND. Changing velocities means it is NON-uniform motion - this means the object is accelerating. m/s 2 m/s /s OR = ∆t∆t ∆v∆v a P(m)
Velocity and Speed. Mechanics Branch of physics that studies motion Two parts Kinematics – describes motion Dynamics – tells why motion occurs.
Motion Review. What is the difference between an independent and dependent variable?
Ch 2 Velocity ~Motion in One Dimension~. Scalar versus Vector Scalar – quantity that only has magnitude Vector – quantity that has magnitude and direction.
Section 2.4 Graphs of Motion. Why Use Graphs? Show relationships between distance, velocity, acceleration, and time Visual and clear way of representing.
Section 1Motion Bellringer, continued 1. For each of the devices above, indicate whether it measures distance, time, or speed. 2. For each of the devices.
Section 1Motion Bellringer, continued 1. For each of the devices above, indicate whether it measures distance, time, or speed. 2. For each of the devices.
Ch. 2 Graphing of Motion in One Dimension. Displacement-time Graph (  x vs.  t) Slope equals velocity. The "y" intercept equals the initial displacement.
Kinematics Equations Just what you have been waiting for…more math!
Motion Chapter 11.
Motion Graphs Let’s go over the basics.. Acceleration vs. time graphs (a vs. t) These graphs are boring, and will only have a straight line above the.
Acceleration Acceleration – the rate at which velocity changes  Can be an: Increase in speed Decrease in speed Change in direction.
Chapter 2: Linear Motion Kinematics. Kinematics Kinematics is the science of describing the motion of objects using words, diagrams, numbers, graphs,
Chapter 3 Accelerated Motion. Introduction In this chapter we will examine acceleration and define it in terms of velocity. We will also solve problems.
READ PAGES Physics Homework. Terms used to describe Physical Quantities Scalar quantities are numbers without any direction Vector quantities that.
Constant, Average and Instantaneous Velocity Physics 11.
1.1Motion and Motion Graphs. Kinematics Terminology Scalar vs. Vector Scalar: quantities that have only a size, but no direction – ie: distance, speed.
Acceleration Physics Montwood High School R. Casao.
Graphical Model of Motion. We will combine our Kinematics Equations with our Graphical Relationships to describe One Dimensional motion! We will be looking.
Motion graphs Position (displacement) vs. time Distance vs. time
Graphs of a falling object And you. Objective 1: Graph a position –vs- time graph for an object falling from a tall building for 10 seconds Calculate.
Describing and Measuring Motion When is an object in motion? How do you know an object’s speed and velocity? How can you graph motion?
Motion in One Dimension: Position vs Time
Graphical Interpretation of Motion in One Dimension
Velocity and Speed Graphically
Non-Constant Velocity
Kinematics Formulae & Problems Day #1
Section 1 Displacement and Velocity
Motion in One Dimension
Aim: How do we analyze position-time or Displacement-time graphs?
The resulting position-time graph would look like this.
Velocity-Time Graphs for Acceleration
The resulting position-time graph would look like this.
Presentation transcript:

First jet powered man to cross English channel Sept 26, 2008 Position vs Time Graphs Examine the data table of a plane in flight shown below:plane Time (s)Position (m) Is the plane travelling at a constant speed? It is actually a little difficult to tell by just looking at the data. You could try to calculate the velocity during each successive time interval … but this becomes cumbersome.

Position vs Time Graphs There is a much easier way. Scientists use this method all the time to see if a relationship between two variables exist! That’s right … it is our old friend the GRAPH! Let us Plot a graph of position vs. time and see what comes out Do the “Toy Tractor Lab”

Position vs Time Graphs The plot of the plane data yields the following graph: The visual picture of the graph (the straight line) tells us that the plane is travelling at a constant speed. It is easy to see this when the data is plotted on a graph.

Position vs Time Graphs Let us look at this graph one more time : Let’s determine the slope of this graph. Slope = rise/run Slope = Δd/Δt ΔdΔd ΔtΔt But wait: We have seen this equation before!

Position vs Time Graphs PositionPosition Time A B C Does each of these lines show constant (uniform) velocity ? What is the difference between A & B?

Position vs Time Graphs Remember this equation: v ave = ΔdΔd ΔtΔt Look at the slope equation: Slope = ΔdΔd ΔtΔt They are the same equation!!! The slope of a Position vs Time graph is the same as the velocity (speed) of the object! Slope = = 260 m/s v ave = For the plane:

Position vs Time Graphs Since the slope equals velocity and the slope is constant (straight line) the velocity of the plane must be constant too! Important fact: Straight line Position vs Time graphs (constant slope) show constant velocity sometimes called “Uniform Motion”!

Position vs Time Graphs A C B D E What kind of motion does each of the lines represent? Position (m) Time (s) 0 0

Positive and Negative Velocities AB Car A is moving to the right at 5.0 m/s Car B is moving to the left at 7.0 m/s We could also say Car A has a +5.0 m/s velocity. And Car B has a -7.0 m/s velocity. In kinematics + and – have directional meanings. It indicates the direction that an object is moving

Position vs Time Graphs How are positive and negative velocities shown on a position vs time graph? Position (m) Time (s) 0 0 A B C D E What is happening during each of the labeled intervals?

Position vs Time Graphs Position (m) Time (s) 0 0 What would this graph mean? This would be impossible!! This line implies that you have infinite speed or you are at more than two places (infinite places) at the SAME time!

Position vs Time Graphs Other kinds of graphs: What kind of motion is being shown on each onekind of motion P t 1 P t 2 P t 3 P t 4

Position vs Time Graphs Position (m) Time (s) 0 0 Calculating Average Velocities: 1) Select two points that you are interested in 2) Connect your two points with a straight line 3) Calculate the slope of this line ΔdΔd ΔtΔt v ave = ΔdΔd ΔtΔt The slope of a line connecting two points on a position vs time graph is called the average velocity.

Position vs Time Graphs Do “Displacement vs. Time Graph“ Activity

Position vs Time Graphs Instantaneous Velocities (The “right-now” speed) Its great to know your average speed but sometimes you need to know your exact speed at a point in time. This absolutely critical to the pilot of an airplane at take and landing or a race car going around a corner or the exact speed of a bearing in a power plant How can you use your position vs. time graph to find this instantaneous speed?

Position vs Times Graphs Position (m) Time (s) For constant velocity situations (straight line) the instantaneous velocity and average velocity are the same!

Position vs Time Graphs P t But what happens when your velocity is not constant? The line is a curve which means the velocity is always increasing! There is not a single value for the velocity. We could calculate the instantaneous velocity or the velocity at a given point.

Position vs Time Graphs P t Calculating Instantaneous Velocities: 1) Select the time, t 1, that you are interested in t1t1 2) Draw in a “tangent line” at that point. 3) Calculate the slope of this tangent line ΔtΔt ΔdΔd v = ΔdΔd ΔtΔt

Position vs Time Graphs  Time to do a little Hands on Activity:  Accelerating Cart Down a Ramp Lab

Position vs Time Graphs