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IAN pg. 69. Velocity & Acceleration. Objective: Define and calculate acceleration and velocity using notes, graphs and calculations. TERMS TODAY 1. Velocity 2. Acceleration 3. Deceleration. III. Velocity. A. Velocity = measure speed and direction.
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IAN pg. 69 Velocity & Acceleration Objective: Define and calculate acceleration and velocity using notes, graphs and calculations. TERMS TODAY 1. Velocity 2. Acceleration 3. Deceleration
III. Velocity A. Velocity = measure speed and direction. 1. Velocity is a vector! (It has size & direction) Ex. 45 mph to the west 18 meters/sec to the north
a. Speedis a scalar quantity (Size Only). b. Velocityis a vector quantity (Size & Direction).
TOP 1/2 IAN pg. 68 Illustrate your own example of velocity. Make your drawing neat and colorful. Include the speed and direction of your object.
II. Acceleration A. Acceleration measures the rate at which velocity changes over time.
1. Acceleration occurs when an object speeds up and/or changes direction 2. Decelerationoccurs as an object slows down and/or changes direction
Acceleration is a change in velocity Velocity is speed and direction. Velocity is a vector quantity.
Bottom Half IAN pg. 68The three ways an object can accelerate • Acceleration in the Same Direction as Motion • Deceleration in the Opposite Direction of Motion • Acceleration in a different direction to Motion
3. The formula for acceleration is: final speed - original speed time in change of speed a = OR Vf – Vi T • Acceleration is expressed in units of Distance/Time/Time EX. m/s/s or m/h/h a =
IAN pg. 70 Ex. A Car goes from 20 km/hr to 40 km/hr in 10 seconds, What is the cars acceleration? a= 2 kilometers per hour per second This means that every second the car travels it is increasing its speed by 2 km/hr a = Vf – Vi T a = 40km/hr – 20km/hr 10 sec a = 20km/hr 10 sec a = 2 km/hr/sec
IAN pg. 70 Ex. A Car goes from 40 km/hr to 0 km/hr in 8 seconds, What is the cars acceleration? DECELERATION! This means that every second the car travels its decreasing its speed by – 5 km/hr. a = Vf – Vi T a = 0km/hr – 40km/hr 8sec a= -40km/hr 8 sec a = - 5 km/hr/sec
IAN PAGE 70 VELOCITY TIME GRAPHS
IAN PAGE 70 Velocity Time Graphs • Traveling at a constant speed would look like this: • A motion diagram would look like this: • Positive Acceleration would look like this: • A motion diagram would look like this:
IAN PAGE 70 More Velocity Time Graphs • Negative Acceleration would look like this: • A motion diagram would look like this: • What about a graph with two lines? • Both lines reach the same speed, but the yellow one gets there first, it has greater acceleration.