1. Speed, Velocity, and Acceleration

2. Speed Speed: how fast something is moving  Ex 1: A racecar travels at 90 miles per hour (mi/hr)  Ex 2: A runner runs at 15 kilometers per hour (km/hr)  Ex 3: A ball rolls across the floor at 5 meters per second (m/s) Average Speed = Total Distance Total Time

3. Triangle Method What is the average speed of a car that travels 100 miles in 2 hours?

4. Algebraic Method A car is moving at a speed of 60 miles per hour for 3 hours. How far did the car go? Average Speed = Distance Time

5. Average Speed Example A track runner runs 50 meters in 10 seconds. What is his average speed?

6. Another Example The average speed of a race car was 20 meters per second. The car took 4 seconds to complete the trip. How FAR did the car go?

7. One more… Mr. Albano ran 9 miles yesterday at an average speed of 10 miles per hour. How long (time wise) did he run for?

8. Average Speed vs. Instantaneous Speed Average Speed = Total Distance Traveled ÷ Total Time  Average Speed is the speed an object averaged over a set period of time. Instantaneous Speed: speed at which an object is moving at a single point in time Like watching the speedometer in a car! Example: A runner averaged 9 mi/hr for 1 hour. At a moment he was running uphill, his instantaneous speed was 6 mi/hr. What might his instantaneous speed have been for a moment while running downhill?

9. Velocity Velocity: speed in a given direction Just like speed but it ALSO gives information about direction Examples: Billy sailed his boat NORTH at 10 meters per second. Ronda drove 55 miles per hour SOUTH on route 23.

10. Velocity Example Two cars travel in the same direction from the same starting point. One goes at an average velocity of 10 meters per second. The other travels at 15 meters per second. They both go for exactly 5 seconds. How far apart are they?

11. Another Velocity Example You race your friend on your bike. Your friend’s average velocity was North at 3 meters per second and they stopped at the finish line in 30 seconds. You were confused and rode SOUTH at 4 meters per second. You rode for 3 seconds before you stopped, realized your mistake, and gave up. How far are you from your friend?

12. One more… Two cars start driving from the same location. One goes 30 miles per hour for 2 hours, and the other one goes 50 miles per hour for 2 hours. How far apart are they? Can’t figure it out?? Tell me what is WRONG with this example! Now solve it as if they were moving in opposite directions!

13. What’s the hint? Velocity Problems – when given velocity and time – Same direction = you SUBTRACT the distances to tell how far apart the objects are – Opposite direction = you ADD the distances to tell how far apart the objects are