Ch

TrueFalseStatementTrueFalse A frame of reference is objects moving with respect to one another Distance is the length between 2 points and the direction Displacement is the added length of all points and the direction To add straight displacements you add the vectors To add non straight lines you use the resultant vector and Pythagoreans theorem

 Helps describe motion accurately and completely  A system of objects NOT moving with respect to one another  Relative Motion  Movement in relation to a frame of reference  Ex: Train ▪ Platform- people on train are moving ▪ In train- people are not moving

 Distance= the length of a path between 2 points  SI Unit- meter kilometer- large distance centimeter- small distance

 Displacement= direction from start point and length of a straight line from start to end point  Travel 5 blocks north of the bus stop

 Vector= quantity that has magnitude and direction  Magnitude= size, length, or amount  Shown as arrows on maps/graphs  Add displacements by adding vectors

 Add magnitudes if  2 vectors have same direction  Ex: 1 st car magnitude= 4km(pg 330) 2 nd car magnitude= 2 km Both traveling same direction = ____ km displacement Opposite traveling direction = ____km displacement

 Add total distance  Draw resultant vector  Vector sum of 2 or more vectors  Also displacement  Pg 331- Walked 7 blocks Displacement= 5 blocks NE

 a 2 + b 2 = c 2  Find distance traveled and displacement

Ch. 11.2

TrueFalseStatementTrueFalse Speed is distance/time and the SI unit is m/s Velocity is speed with direction and the SI unit is m/s 2 Velocity has the same formula as speed Because velocity is a vector we can use Pythagoreans Theorem The slope of a distance time graph is velocity

 Speed= the ratio of the distance an object moves to amount of time the object moves  SI Unit- meters per second m/s km/h  2 Types of Speed

AVERAGE SPEED  Speed computed for entire duration of trip  v = d t INSTANTANEOUS SPEED  Speed at a particular instant  Can tell you how long your trip will take  Speedometers

While traveling on vacation, you travel 35 km in 0.4 hours, then 53 km in 0.6 hours. What is your average speed? 1. Given Info Total distance: Total time: 2. Solve need speed 3. Plug and chug 4. Check

1. 2.

 Slope of a line on a distance-time graph is speed  Pg 334  Calculate slope of  A=  B=  C=

 Velocity= the speed and direction in which an object is moving  Description of BOTH speed and direction  Vector  Change in velocity  Change in speed, direction or both

Race car traveling 120 km/h Speed, direction, velocity?

 2 or more velocities added by vectors  River= 5 km/h  Boat= 12 km/h  Total velocity=  pg. 337  River= 5 km/h  Boat= 12 km/h  Total Velocity=

Ch. 11.3

TrueFalseStatementTrueFalse Acceleration is a change in speed, direction or both a = vi – vf t An object slowing down is accelerating An object in a circle, at constant speed is accelerating Acceleration can be a time-speed graph or distance-time graph

 The rate at which velocity changes  Changes in speed, direction or both  vector

CHANGE IN SPEED  Increase or decrease in speed  Free fall- movement of object toward Earth due to gravity(9.8m/s 2 )  SI unit- m/s 2 CHANGE IN DIRECTION  Speed can be constant, but a change in direction yields acceleration

CHANGE IN SPEED & DIRECTION CONSTANT ACCELERATION  Steady change in velocity

A ball rolls down a ramp, starting from rest. After 2 seconds its velocity is 6m/s. What is the acceleration of the ball? 1. Given Info Time- Vi- Vf- 2. Plug and Chug acceleration-? 3. Check

 1.  3.  2.  4.

 Slope of speed-time graphs is acceleration  Change in speed divided by change in time

SPEED-TIME GRAPH  Linear graphs DISTANCE-TIME GRAPH  Nonlinear graphs

 How fast a velocity is changing at a specific instant

Motion displacement acceleration direction Change in speed