Take out a blank sheet of paper label
Take out a blank sheet of paper, label it Page 105: Speed and Acceleration Notes
Reviewing the definitions… Speed – a measurement of how quickly your position is changing Acceleration – a measurement of how quickly your speed is changing
Reviewing the definitions… Speed – a measurement of how quickly your position is changing Acceleration – a measurement of how quickly your speed is changing
Reviewing the definitions… Speed – a measurement of how quickly your position is changing Acceleration – a measurement of how quickly your speed is changing
Calculating Speed: s = speed d = distance t = time Common Units: miles per hour (mph) kilometers per hour (km/hr) meters per second (m/s) knots (for boats) feet per second (ft/s) mach number (for airplanes)
Calculating Speed: s = speed d = distance t = time Common Units: miles per hour (mph) kilometers per hour (km/hr) meters per second (m/s) knots (for boats) feet per second (ft/s) mach number (for airplanes) Example Problem: 450 feet
Calculating Acceleration: a = acceleration ∆s = change in speed t = time Common Units: miles per hour per second (mph/s) meters per second (m/s 2)
Calculating Acceleration: a = acceleration ∆s = change in speed t = time Common Units: miles per hour per second (mph/s) meters per second (m/s 2) Example Problem: 60 mph 3 seconds later… 66 mph
Calculating Acceleration in Class: Assumptions: • All you have is a stopwatch • Speed starts at zero • Object accelerates steadily a = acceleration 20 feet d = distance t = time
Reviewing what we learned… • What are speed and acceleration? • How do you calculate average speed? • How do you calculate acceleration in class? is changing
Practice problems… 1. On a flight from Boston to Los Angeles, you will cover a distance of about 2, 600 miles. Typically, that flight takes about 6 hours. What is average speed of the airplane? 2. On her most recent drive to Syracuse, Mrs. Delaney got pulled over for speeding. She got onto the highway going about 50 mph, and 30 seconds later, the police clocked her at 78 mph. What was her acceleration during that time? 3. Usain Bolt can run 100 meters in 9. 58 seconds. But ironically, he only accelerates for the first 60 meters of the race, a distance that he covers in about 6. 3 seconds. What is his acceleration during the first 60 meters of the race? the
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