Day 22 3/3/2011 objective: Finish data collection for human runners then produce a position versus time and velocity versus time for all six motions (12 graphs all together). Students will print one of the twelve and graphs and describe the results (in front of the class if they’re brave).
Finish data collection for human runners then produce a position versus time and velocity versus time for all six motions (12 graphs all together). Students will print one of the twelve and graphs and describe the results (in front of the class if they’re brave).
Warm up: Observe the ‘Human Motion’ graph and table. Fill in the velocity column then produce the velocity versus time graph. Then produce a narrative (a story) that would fit with the motion.
Finish producing all motion graphs from human runners in Excel then discuss
Observe and discuss ‘clean’ version of accelerated motion generated with motion detector and identify important points (max + velocity, max – velocity, zero velocity, initial position, final position, acceleration, etc).
Vocabulary: m/s/s, meters per second per second, m/s2
Warm up: What does a straight line mean on a d vs. t graph? What does a curved line mean on a d vs. t graph? What does the slope of a d vs. t graph tell you? What does the slope of a v vs. t graph tell you?
Finally wrap up human runners
Dress rehearsal lab for test #3: produce two motion graphs (d vs. t and v vs. t) for a ball accelerating down a ramp then decelerating along a flat surface. Describe and explain the results.
Vocabulary: apex, zenith, crest
Warm up: Describe the three ways you can accelerate and then give an example of each.
Share scores from multiple choice
Begin unit on accelerated motion
Measure a famous physical constant: acceleration due to gravity.
Warm up: Use the following three equations
Vaverage = d/t
Vfinal = 2 Vaverage
a = (Vfinal – Vinitial)/Δt
to find distance as a function of acceleration and time.
Shuffleboard: Find the acceleration of a book sliding along the floor. See how the initial velocity provided by your push affects the acceleration
Vertically launched marble: Use hang time to predict the altitude of a vertically launched projectile, then check your prediction with reality.
Vocabulary: free fall
Warm up: Write two acceleration problems, one free fall and one car crash and solve.
Start the distracted driver lab (how mass affects acceleration down a ramp and acceleration during a car crash).
Finish vertically launched projectiles
More boring practice problems
Warm up: Drop a ball from a known distance and calculate the impact velocity. After impact measure the hang time of the ball and find the rebound velocity. Compare the impact velocity to the rebound velocity? What causes the change in velocity?
Galileo had the leaning tower of Pisa and we have the bleachers (using fall time to determine fall distance and impact velocity)
Vertically launched taters (using hang time to determine muzzle velocity and maximum altitude)
Warm up: What measurements/assumptions will you make by the bleachers? What calculations will you perform? What measurements will you make for the potato gun?
Wrap up vertically launched projectiles (muzzle velocity and altitude as a function of hang time)
Do high-tech version of the distracted driver (acceleration down a ramp and during a car crash as a function of vehicle mass)
Vertically launched humans (using hang time to predict vertical leap)
Vocabulary: hang time
Warm up: Do a sample calculation from Friday’s labs (one for the bleachers and a second for the taters).