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HW DuePlace both in In Box (POGIL page 2 and the worksheet)HW Worksheet given out at end of classQuest Jan 23 (B day) ***There is a REALLY GOOD review PowerPoint on my website***Do NowTake one and complete BOTH SIDES.

May work with peers. A bug and the windshield of a fast moving car collide. Tell whether the following statements are true or false, and EXPLAIN your reasoning:

a. The forces of impact on the bug and on the car are the same size.

TrueFalseNot enough infoNot quite sureTRUE!FORCES COME IN PAIRS!A bug and the windshield of a fast moving car collide. Tell whether the following statements are true or false, and EXPLAIN your reasoning:

b. The impulses on the bug and on the car are the same size.

TrueFalseNot enough infoNot quite sureTRUE!SAME FORCE, SAME CONTACT TIMEA bug and the windshield of a fast moving car collide. Tell whether the following statements are true or false, and EXPLAIN your reasoning:

c. The changes in speed of the bug and on the car are the same size.

TrueFalseNot enough infoNot quite sureFALSE!COMMON SENSEDO YOU NOTICE THE CAR SLOW DOWN? DOES THE BUG NOTICE A CHANGE?A bug and the windshield of a fast moving car collide. Tell whether the following statements are true or false, and EXPLAIN your reasoning:

d. The changes in momentum of the bug and on the car are the same size.

TrueFalseNot enough infoNot quite sureTRUE!m v = m v

Not to mention, Impulse = change in momentum, and we already determined they have the same impulse BugWindshield FtFtm vm vSame ImpulseSame change in momentumDiff. masses and velocity changes!Does a larger force always produce a larger impulse on an object than a smaller force? Explain.

Yes No Not enough infoNot quite sureNo not always!!F t = F t(1 N) (100s) = (10 N)(5s) 100 Ns = 50 Ns

YES/NO:____ EXPLANATION:A fully dressed student with a backpack is at rest in the middle of a pond on perfectly frictionless ice and must go to shore. Can this be accomplished?Use KEY TERMS to explain:

Yes No Not enough infoNot quite sureYes throw the backpack! Force = Force, Impulse = Impulse

HW that was due today (workseet)Worksheet Texts open if needed 3 minutes to review with peers in the FRONT of the classroomGossiping/ being off task will result in you going back to your seat and will guarantee the teacher will call on you.Then, we are rapidly popcorning!

QUESTIONS ABOUT24 or 26? A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had a. twice the mass and was moving at the same speed?

TWICE as much!m v = p4 . 6 = 24So.8 . 6 = 48

A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had b. the same mass and was moving with twice the speed?

TWICE as much!m v = p4 . 6 = 24So.4. 12= 48

A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had c. one-half the mass and was moving with twice the speed?

Same!m v = p4 . 6 = 24So.2 . 12 = 24

A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had d. the same mass and was moving with one-half the speed?

HALF as much!m v = p4 . 6 = 24So.4. 3= 12

A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had e. three times the mass and was moving with one-half the speed?

1.5 times as much!m v = p4 . 6 = 24So.12 . 3 = 36

A bicycle has a momentum of 24 kgm/s. What momentum would the bicycle have if it had f. three times the mass and was moving with twice the speed?

6 times as much!m v = p4 . 6 = 24So.12 . 12 = 144

RecapLast class, we talked about impulse changing momentum. This class (and the next 2 classes), we are going to talk about what happens if that impulse occurs during 2 scenarios:When bouncing occursWhen a collision occursPOGIL from last class 10 minutesTake out your notes from last class and go to the demo section. (Nerf Guns, Ping Pong Balls, Toppling)You will be shown the Nerf Gun and Toppling Demos, and you will get to try the Ping Pong Demos. BEFORE THAT. I want you to consider the following question (write & answer in your notes)Would a head-on collision between two cars be more damaging to the occupants if the cars stuck together or if the cars rebounded (bounced) upon collision? (Assume the time of the collision is the same.)

Would a head-on collision between two cars be more damaging to the occupants if the cars stuck together or if the cars rebounded (bounced) upon collision? (Assume the time of the collision is the same.) When the cars stickWhen the cars bounceDoesnt matter either way Not sure!POGIL from last classCross out pages 3 4 look like this:

unless you want to challenge yourself to try what the Geo kids are doingthen, feel free to try them at home and check!

POGIL from last class 10 minutesYou will be shown the Nerf Gun and Toppling Demos, and you will get to try the Ping Pong Demos. Then, working in the FRONT of the classroom, you MUST answer all questions A through FPlease review your HW on the POGIL (page 2)Ensure that EVERYONE understands not only WHAT the solutions are, but WHY they are what they areyou should be able to transfer your thought process to other questions regarding similar concepts. ***NOT SURE/ QUESTIONS? ASK A TEACHER!!!***

Finish part G Conclusion. 10 minutes to complete!When is impulse larger? (heads down hands up)

When objects bounceWhen objects dont bounce Doesnt matter either way Not sure!

BouncingImpulses are greater when bouncing takes placeFt = (mv)Falling flower pot hits your head Momentum stopsFalling flower pot hits your head and bounces off Momentum is reversed. **Impulse to stop < impulse to throw it back again**2(mv)Karate chopPelton wheel

2323BouncingImportant point: It only takes an impulse of mv to stop the ball. It takes twice the impulse (2mv) to make it bounce)

Think about a bouncing ball:Before it hits the ground:Speed = vMomentum = mvAt the moment it hits the ground:Speed = 0Momentum = 0After it leaves the ground:Speed = vMomentum = mvImpulse needed to stop the ball = mvTotal Impulse = 2mvImpulse needed to accelerate the ball upwoard = mv

Just like the medicine ball exercise!!!

If the time of impact is long, the force will be milder. If the time is very short, the force is powerful. When things bounce off an object after hitting them, it is even more deadly in force magnitude.The physics term forBOUNCEis REBOUNDA rebound is a special type of collision involving: A rebound is a special type of collision involving: a direction change which results in a velocity change. A rebound is a special type of collision involving: a direction change which results in a velocity change. Observe that the greater therebound effect, the greater theA rebound is a special type of collision involving: a direction change which results in a velocity change. Observe that the greater therebound effect, the greater theacceleration, momentum change, and impulse.

A rebound is a special type of collision involving: a direction change which results in a velocity change. Observe that the greater therebound effect, the greater theacceleration, momentum change, and impulse.

The result of the direction change is a large velocity change.

HW that was due last class#11-13, p. 100 Texts open if needed 3 minutes to review with peers in the FRONT of the classroomGossiping/ being off task will result in you going back to your seat and will guarantee the teacher will call on you.Then, we are rapidly popcorning!

HW that was due last class#11-13, p. 100 Texts open if needed we are rapidly popcorning!

11a) Visualize yourself on a skateboard. When you throw a ball, do you experience an impulse?

Yes push the ball, and ball pushes you (force) for an amount of timeforce x time = impulse!

HW that was due last class11b) Visualize yourself on a skateboard. When you catch a ball, do you experience an impulse?

Yes push the ball, and ball pushes you (force) for an amount of timeforce x time = impulse!

HW that was due last class11c) Visualize yourself on a skateboard. When you catch a ball, and then throw it back, do you experience an impulse?

Yes push the ball, and ball pushes you (force) for an amount of timeforce x time = impulse!

HW that was due last class11d) Visualize yourself on a skateboard. In which of the scenarios do you experience the largest impulse?CatchThrowCatch an throwSame in all

Catch and throw its like bouncing! More velocity change, so more momentum change, so more impulse!

HW that was due last class12) Why is more impulse delivered when bouncing occurs?

More velocity change, so more momentum change, so more impulse!

Go to your test seatsNormal quiz procedures applyOpen notes, not open booksNo calc needed cell phones OUT and SILENTWhen done, quiz in basket upside down and you may continue working on your HW(make your hypotheses and try them)Open notes quest on Ch. 7 on Jan. 23

HW that was due last class13) Why is the Pelton wheel an improvement over a wheel with flat blades?

Go to your test seatsNormal quiz procedures applyOpen notes, not open booksNo calc needed cell phones OUT and SILENTWhen done, quiz in basket upside down and take a copy of your:Momentum Conceptual review (HW)Start working on this it is HW!!!And Midterm InformationRead the Midterm Information sheet tonight we will answer any questions about it next class