QQ: Brandon’s velocity starts at 0, increases rapidly for the first few seconds, then after reaching 11 m/s remains almost constant. Find his velocity at 1 second. At 2 seconds? At 3 seconds?

Today’s objective: I can calculate average and instantaneous acceleration mathematically.

Because there is a change in velocity, there is acceleration Because there is a change in velocity, there is acceleration. At what point in the graph is the acceleration the greatest? The least?

Calculate the acceleration at t = 1 s. 8m/s = 4 m/s2 2 s

Calculate the acceleration at t = 3 s.

Because the slopes are not equal, the acceleration is not constant. Notice how the unit for acceleration is m/s2 . Treat the units as numbers or variables to check your units. 4 8 m/s 8 m s 8 m s 1 x = 8 m 2 s2 2s 2 s 2s

This represents the motion of a remote control car This represents the motion of a remote control car. When is the speed a constant?

During which time interval(s) is the train’s acceleration positive?

During which time interval(s) is the train’s acceleration most negative?

Activity: Move around the room in groups of 2 or 3. Solve each of the problems on colored papers. Show your work.