Speed and Velocity 11 2 Calculating Average Speed

Speed and Velocity 11. 2 Calculating Average Speed or Velocity Video Lecture Solving for Time Video Lecture Solving for Distance Video Lecture

Speed n Speed- Ratio of the distance and object moves to the amount of time the object moves. u SI unit for speed is m/s t Always use appropriate units (cm/s, km/hr)

Average Speed- is the total distance traveled divided by the total time n Units: m/s, km/h u Average Speed= Total Distance Total Time t V = d/t n

Instantaneous Speed n Instantaneous Speedthe rate at which an object is moving at any given time. u Tells you how fast something is traveling at this moment. t Speedometer, Radar Gun

Graphing Motion n n A good way to describe motion is with a distance vs. time graph. The slope of a line on a distance time graph is the speed.

Motion Graphs n Varying Speed

Motion Graphs n A straight line represents constant speed = Direct Proportional Effect

Motion Graphs n A curved line represents acceleration = direct exponential

What is velocity? Velocity is a description of both speed and direction n Velocity is a vector n A change in velocity can result from a change in speed or direction or both! n

How can velocities be combined? n By addition! n 5 km/h east + 12 km/h east = 17 km/h east n 10 km/h east + -6 km/h west = 4 km/h east 5 km/h n n n a 2 + b 2 = c 2 122 + 52 = c 2 144 + 25 = c 2 √ 169 = √c 13 = c 12 km/h c