Chapter 11 Motion You will need a calculator for this chapter!
Slide 2 Section 11.1 Distance and Displacement p. 328 Slide 3 What
is a frame of reference? What is a frame of reference? How fast was
the boat traveling? Relative to what? Motion must be described
relative to a frame of reference relative motion Relative to Earths
surface (understood) Slide 4 How fast was the boat traveling?
Relative to spectators? Really Fast!!!! Relative to driver? ZERO!
Driver & boatsame frame of reference Tennis ball ex(p.329)
Einsteins Theory of Relativity 10:06 Slide 5 Choosing a Frame of
Reference Conclusion?? The Frame of Reference determines how motion
of an object is described. Slide 6 Measuring Distance Distance -
length btwn 2 pts SI unit.meter (m) Derived units cm (snail
crawling) km (distance btwn 2 cities) Slide 7 Measuring
Displacements distance v.s. displacement? walk 5 blocks (distance )
walk 5 blocks north from the bus stop (displacement) direction
& distance from start to end Displacement needed for accurate
directions Slide 8 Combining Displacements Vector? Measurement w/
magnitude and direction Magnitude? Size, length, amount Described
w/ Slide 9 Displacement along a straight line 2 vectors same
direction Add magnitudes Ex. A car travels 10 km north, stops to
refuel, then travels 20 km north total distance = 30 km total
displacement = 30 km (10 km north + 20 km north) from starting pt
Slide 10 Displacement along a straight line 2 vectors. opposite
directions Subtract mags Ex. Bicyclist travels 5 km east, turns
around and travels 3 km west Bicyclists total distance = 8 km total
displacement = 2 km east (5 km 3 km) Slide 11 Displacement That
isnt along a straight path 2+ vectors w/ different directions
Combine by graphing graphing Resultant vector - sum of all vectors
Shows distance & displacement related but different Slide 12
Section 11.1 Assessment What is a frame of reference? How is it
used to measure motion? How are distance and displacement similar
and different? How are displacements combined? A girl who is
watching a plane fly tells her friend that the plane isnt moving at
all. Describe a frame of reference in which the girls description
would be true. Slide 13 Section 11.1 Assessment Should your
directions to a friend for traveling from one city to another
include displacements or distances? Explain your choice. A spider
is crawling on a wall. First it crawls 1 m up, then 1 m to the
left, and then 1 m down. What is the distance the spider crawled?
What is the spiders displacement? Slide 14 Section 11.2 Speed and
Velocity p. 332 Have your calculator on your desk Slide 15 Video
Can you describe the speed of the skaters? What information is
needed to determine the speed of the skaters? Speed - ratio of
distance traveled to time needed to travel that distance. SI unit
meters per second (m/s) derived units: km/hr cm/s Slide 16 Average
speed entire duration of a trip, average speed - total distance
traveled (d), divided by total time (t) Average Speed = total
distance total time total timeOr.. Calculating average speed Math
Skills p. 333 Calculating average speed Math Skills p. 333 Slide 17
Average Speed ( v ) Avg speed doesnt reflect most common speed of
trip stops, curves, hills Useful tells how long trip will take If v
is 60 mi/hr & destination is 120 mi, your TOA is 2 hours
Calculating average speed Math Practice p. 333 Calculating average
speed Math Practice p. 333 Slide 18 Instantaneous speed
Instantaneous speed (v) - rate object is moving at given moment
speedometers show instantaneous speed 100 mi/hr (160 km/hr) Slide
19 Distance-time graph Slope = change in vertical axis change in
horizontal axis change in horizontal axis Slope is speed of object
plottedSlope is speed of object plotted Graphing Motion Slide 20
Slope (rise/run) = speed Calculate: What can you conclude about the
speed of the RC car? Distance v.s. Time of an RC car Slide 21
Graphing Motion 4 segments (A-D) to find average speed for each
segment Calculate: Describe the speed of the car in segment B?
Driving speed of a car in rush hour traffic A D C B Distance-time
graph Distance-time graph Slide 22 Velocity Pilots and control
tower communicate describing velocity of planes Velocity describes
speed and direction vector v changes if speed, direction, or both
change Slide 23 Velocity Car traveling at constant speed (55 mi/hr)
How would you describe its velocity? Direction changing on circular
track, velocity changing Slide 24 Changing Velocities When
velocities in same direction, add together River velocity= 7km/hr
east Boat velocity= 16km/hr east 16 km/hr east 7 km/hr east
Calculate: Slide 25 Changing Velocities When velocities at rt
angles, use Pythagorean theorem to solve plane= 400km/hr west wind
speed= 25km/hr south a 2 + b 2 = c 2 Calculate: 25 km/hr south 400
km/hr west Science of NHL hockey vectors 4:29 Slide 26 Section 11.2
Assessment You and a friend are watching a baseball game on ESPN
where the commentator says the pitchers velocity of 100 mi/hr is
virtually unhittable. Your friend agrees. What do you think? What
does the slope on a distance-time graph indicate? Slide 27 Section
11.2 Assessment Does a cars speedometer show instantaneous speed,
average speed, or velocity? Explain. An Olympic swimmer swims 50.0
meters in 23.1 seconds. What is his average speed? Slide 28 Section
11.2 Assessment A planes average speed between two cities is 600
km/hr. If the trip takes 2.5 hours, how far does the plane fly?
Slide 29 Section 11.2 Assessment A discus thrower threw his disc
139 meters through the air. While in flight, the disk traveled at
an average speed of 13.0 m/s. How much time did the disk remain in
the air? Slide 30 Section 11.3 Acceleration p. 342 Suzuki Hayabusa
Suzuki Hayabusa Have your calculator on your desk Slide 31 What is
acceleration? Remember velocity is speed w/ direction Acceleration
- rate velocity changes Vector What is a rate? it takes it takes
time Slide 32 Changes in speed green stoplight car moves forward
acceleration (positive change in cars speed) pushes you back in
seat red stoplight speed decreases (negative change) you fall
forward towards dash vectors_car_velocity_accel.notebook Slide 33
Free-Fall Free-fall - acceleration toward Earth b/c gravity
Speed/velocity SI units is m/s Units for acceleration - meters per
second per second or m/s 2 The 2 nd second is time needed to time
needed to change speed (rate) change speed (rate) Slide 34
Free-Fall a near Earth = 9.8 m/s 2 bungee jumper will accelerate
9.8 meters per second every second hes in FF 1 s of FF speed = 9.8
m/s 2 s of FF speed =19.6 m/s (sped up 9.8 m/s in 1 s) What is
speed after 3 s? 29.4 m/s after 3 seconds Slide 35 If the Earth is
moving, why can I not feel it? body detects changes in speed Earth
spin constant speed 850 mi/hr at mid latitudes (faster at equator)
Revolves 67,000 mi/hr 2x bullet speed! 1.6 million miles / day!
WOW!!! Slide 36 Changes in Direction a occurs if direction changes
even if speed constant Ferris wheel & carousel = constant speed
accelerate b/c change direction Slide 37 Changes in speed and
direction roller coasters winding roads Slide 38 Constant
Acceleration straight line motion & speeding up / slowing down
- constant acceleration v of object changes same amt each sec Indy
car pulling Gs 3:00 Slide 39 Calculating Acceleration calculate
acceleration for straight-line motion using this equation:
Acceleration = change in velocity total time total time or.. (v f v
i ) t Velocity and acceleration 1:58 Velocity and acceleration 1:58
(v f v i ) a x t a x t venn diagram review.notebook Slide 40 Slide
41 Math Practice #1 p. 346 A car traveling at 10 m/s starts to
decelerate steadily. It comes to a complete stop in 20 seconds.
What is its acceleration? Slide 42 Math Practice #2 p. 346 An
airplane travels down a runway for 4.0 seconds with an acceleration
of 9.0 m/s 2. What is its change in velocity during this time?
Slide 43 Math Practice #3 p. 346 A child drops a ball from a
bridge. The ball strikes the water under the bridge 2.0 seconds
later. What is the velocity of the ball when it strikes the water?
Slide 44 Math Practice #4 p. 346 A boy throws a rock straight up
into the air. It reaches the highest point of its flight after 2.5
seconds. How fast was the rock going when it left the boys hand?
(acceleration is downward b/c of gravity, but velocity is upward)
Slide 45 Acceleration of a Mercedes-Benz Acceleration of a
Mercedes-Benz Volunteer timers we will average the times How much
time does it take to go from 0 km/hr to 200 km/hr? Slide 46 Graphs
of Accelerated motion Speed-time graph displays acceleration Slope
of speed-time graph is acceleration of object Slide 47 Slide 48
Distance-Time Graphs Accelerated motion is represented by a curved
(non-linear) line on distance-time graph Slope (speed) greater
after 3 sec than 1 sec acceleration video 3:24 acceleration video
3:24 Slide 49 Instantaneous Acceleration Instantaneous acceleration
(IA) - how fast velo changing at specific instant Skateboarder
continually changes speed & direction his IA always changing
Slide 50 Instantaneous Acceleration Vector of skateboarders
acceleration can point any direction Vector length represents how
fast velocity is changing IA even if standing still and
acceleration vector zero Slide 51 Section 11.3 Assessment Describe
3 types of changes in velocity. What is the equation for
acceleration? What does the slope on a speed-time graph show?
Define instantaneous acceleration.
