Motion Velocity Acceleration Speed vs Velocity https www

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Motion Velocity & Acceleration

Motion Velocity & Acceleration

Speed vs. Velocity • https: //www. youtube. com/watch? v=DRb 5 PSx. Jer. M

Speed vs. Velocity • https: //www. youtube. com/watch? v=DRb 5 PSx. Jer. M

Velocity Definition • How far an object moves in a given amount of time

Velocity Definition • How far an object moves in a given amount of time AND the direction + • velocity = displacement / time • v = (d 2 – d 1)/ t OR Δd / t OR df - di/ t

Pulling It All Together • Back to our ant explorer! - + 5 s

Pulling It All Together • Back to our ant explorer! - + 5 s 0 cm 1 • • 2 3 4 5 6 7 8 Distance traveled: 7 cm Displacement: +3 cm Average speed: (7 cm) / (5 s) = 1. 4 cm/s Average velocity: (+3 cm) / (5 s) = +0. 6 cm/s 9 10

Constant Velocity Lab

Constant Velocity Lab

Acceleration

Acceleration

Change in Velocity • You are at a stoplight and the light turns green

Change in Velocity • You are at a stoplight and the light turns green so you step on the gas petal. How is the car’s speed changing? What happens to the speedometer? • You come to a stop sign and apply the brakes. How is your speed changing? What happens to the speedometer? • Acceleration- The rate of change of velocity.

A Change in velocity can be either: • A change in speed OR •

A Change in velocity can be either: • A change in speed OR • A change in direction • A merry-go round is running at a constant speed. • What is happening to the velocity? Why? • Is there acceleration? Why?

Acceleration Equation acceleration= final velocity- initial velocity time a = (vf – vi) t

Acceleration Equation acceleration= final velocity- initial velocity time a = (vf – vi) t units = m/s 2

A car traveling at 6 m/s slams on the breaks to avoid hitting a

A car traveling at 6 m/s slams on the breaks to avoid hitting a deer. The car comes to a safe stop 6 seconds after applying the breaks. What is the car’s acceleration? a = v f - vi time = 0 m/s – 6 m/s 6 seconds

A car traveling at 6 m/s accelerates to 9 m/s in 3 seconds. What

A car traveling at 6 m/s accelerates to 9 m/s in 3 seconds. What is the car’s acceleration? a = v f - vi time

Positive acceleration Negative acceleration

Positive acceleration Negative acceleration

Velocity Graphs 1. I have 2 lines representing movement plotted on a position graph.

Velocity Graphs 1. I have 2 lines representing movement plotted on a position graph. How can I tell which line is showing faster movement? 2. On a velocity line graph, how can I tell if the walker sped up? 3. On a velocity line graph I see a straight line that is flat – parallel to the bottom of the graph – what can I say about the walkers movement?