 So here's my momentum tutorial questions from the review number 14 That one there Clip this one Troy Okay collision Momentum, so I think the first thing that I would do is go the sum of All the momentum before the collision equals the sum of all the momentum after the collision Before the collision what was moving that's one that's two or both so I'm gonna have Momentum of mass one initial After the collision what's moving that's one mass two or both stuck together. I got less than separately though mass one final and That's to find angles Yeah, see if not I can just go to numbers and cross multiply and do a little bit arithmetic, but okay angles picture dull Here's mass one Incoming looks like it's due east or right. They didn't give me a northeast to the right And its momentum is mass times velocity. I can't just put the velocity on here I got to put momentum on here Momentum is mass times velocity that I can do in my head half of 2.4 at the initial momentum is 12 as 1.2 to the right equals Afterwards my momentum looks like this momentum one final is that way Where this is a 30 degree angle and momentum is what times what? So I got the velocity. Here's the mass. I think here the final momentum is 0.9 plus the mystery momentum and I'll call it momentum to Final and the angle that they want me to find is that one there. I'll see where that ends up appearing in my triangle. Oh How do I add two vectors together draw them? Tip to tail so I will here's the nice thing when I draw these tip to tail I know the answer says both. It's supposed to give me a triangle exactly horizontally That's how I know how to draw my vector triangle. I know that if I go 0.9 plus mystery final momentum It has to give me an answer of exactly horizontal 1.2 Where this angle here is 30 degrees? Sorry, I'm chewing. How can I solve this? So Katoa? Momentum 2 final squared equal 0.9 squared plus plus 1.2 squared minus 2 0.9 times 1.2 Cosine of 30 and then don't forget to square root the final momentum and then square root You get 1.38449 Yeah, I'll go 1.3845. I'm not done. This is the momentum Justin Justin What does the question want me to find not the final momentum? What does it want me to find speed and direction velocity magnitude speed direction theta velocity? If I know the momentum, how can I figure out the velocity? Yeah, momentum is mass time velocity. So and divide by which mass in mass number two That's why you'll notice I've also gotten way more careful in my Labeling and notation. There's lots of room to make sloppy mistakes here as well as the math is pretty heavy. I agree So Gordon, I'll get this Velocity to final is going to be 1.3845 All divided by Is that a 0.3? Yeah, all divided by 0.3. I get a velocity of 4.6 meters per second And I need to act to the direction now Sorry. Oh am I way off in radians? Oh Don't do that. I am in radians Someone should have spoken up. How about you get this? Do you get 0.6159? I wish I'd done that on purpose because that would have been a good teaching moment, but I just had a brain cramp 0.6159 Didn't I say though when I wrote this down? Is that right? Did anybody else get that and nobody said anything? Oh, you were also in radians. Yeah, okay all my all my block D math 12. Yeah, well looks fine Okay, tells me how much homework you did in math 12 and then divide by 0.3 divide by 0.3 How about 2.05? Is that right? 2.05 meters per second at Theta Now it's gonna be looking at the diagram That angle there granted see the Z and to find theta. I can use the sign law It's gonna be the sign of the mystery angle Divided by what's across from it Dylan, which is 0.9 and that equals? the sign of the angle that I do know 30 Divided by the side that I know across from it, which I didn't used to know but now I know is 0.6159 I'll get sign theta equals 0.9 sign 30 all over 0.6159. I am in degrees now 0.9 sign 30 divided by 0.6159. I get that decimal That's the sign of theta. How can I find theta? Inverse sign of that and you don't need to worry in physics 12 about the cast rule or anything like that because we're staying always in physics 12 in the top half of the circle For those of you that are in math 12 so our inverse will work. We're only finding one answer anyways 47 degrees at 47 degrees You could either say below the horizontal. Yeah, I would probably go with northeast south and west and I would call it south of east That is absolutely a question very similar to what you'll see on the test For those of you McDonald's boys who got here late I said I can print this up for you when you guys are done or you can write stuff down. Sorry, okay? 33 What do I want in this case? This is a bit different Brandon. I know the final momentum What do I want the final momentum to be? What word tells me zero? I think you just echoed somebody else Stationary. Why does that help momentum is what times what so if you're stationary? What's your velocity? And since momentum is mass times zero, what's your momentum? So this is a bit different now. They're telling me the final momentum is zero. In fact, here's what I think Brandon I Think if I add this momentum to this momentum vectorially This will be the same magnitude opposite direction. That's what's going to give me the zero So what I'm going to do is take these two and add them together. How will I add them together? So I'm going to go like this four times eight point three 33.2 and add that to I could do that my head two times seven point two mass times velocity 14.4 Now my scale here is terrible really this is half as big as that really I should be drawing a triangle probably like that Okay, with twice as long If you can fit it on your diagram great. How big is this guy? What I want the final momentum to be? End up back where you started from That's going to be R Now thankfully this question is not too bad. Are they wanting theta? Are they wanting the direction or they just want the magnitude? Oh Magnitude and they don't even want the velocity. They just want the momentum. So how can I find the magnitude of that? By Thagoras darn right 14.4 squared plus 33 point two squared Square root Square root 36.2 how else could I ask this instead of asking in the magnitude? I could have just said at what angle? What direction? Okay, so you wouldn't do the Pythagoras you do the trig. I think tangent would get you an angle or I wanted to make a good written question Tell you the massive object are Find the velocity By the way, this is the reverse of an explosion in an explosion We had everything traveling away from the center Can you see all three of these are traveling towards the center? Which is also another way of saying you're gonna get a final momentum of zero an explosion You knew your initial momentum was zero because you knew everything was starting out with a velocity of zero any others 34 am I gonna end up doing all these angle ones for you guys? Are you wanting me to do this or you just want to see if you're right or? Yeah, okay, I'm just a little worried. I'll end up doing all of the angle one I hope you there's more angle ones on your review because I don't want to do them all for you, but okay Well, this is identical to the one you asked me earlier get up Well, it's not yeah Two objects stuck together, but it's gonna be the same idea. I'm gonna start out saying hey collision. Yeah momentum The only difference now is when I ask Before the collision what was moving mass one mass two or both? Well stuck together Then list them separately after the collision. What was moving mass one mass two or both stuck together? Angles are there angles? Draw a little picture if not Dylan you can just go MV MV and both V and cross multiply and subtract and just solve it Like your regular equation angles vector V1 looks like this Plus oh Magnitude can someone go mass times velocity for me, please 4.2 times 1.8 7.56 not rounded off carry it. Oh, yeah. Yeah, okay, and mass two is coming in like this Mystery angle, but we know oh and mystery velocity So I'll just call it momentum to initial Don't know Equals I do know by a rare flute that maths to I'm sorry momentum final Is dead horizontal which is convenient? And Now the velocity is 2.3. What mass am I gonna use here? Both so I'm gonna go 4.2 times 1.3 Sorry times plus 4.2 plus 1.3 mass times Velocity that's got a momentum of 12.65. Is this a final momentum of zero? No, so is this a triangle where you come back to where you started from? Added together tip-to-tail 7.56 mystery Oh, not final. Let's do it initial 12.65 Where's the 30 degrees gonna end up? Bottom top left or top right top left is correct look up. I would do this, right? How big is that? 30 see the Z30 Okay, that's how I draw it then what? Cosine long don't forget to square root How do I find the velocity divide by mass to? Angle angle I would use would be this one right? Oh gosh, Mr. Angle I would use would be This one right here, which is that one right there? So I'll find the magnitude of that angle, but I'll put it here and that would be North of East Think I Really can't do those low drawing a compass Well, it's saying find that angle But what direction is this thing traveling? Is it traveling south of west or which way is it? It's traveling north of east. So you always go back to where your vector is starting from that's where your direction comes from That was quick Okay I'm gonna try and upload this if all goes well if I do I'll email you guys if it doesn't work then I won't Whenever was that Troy? 34 so why don't I be clever and just do this? So there's the same idea 40 um 40 or 40 40 Okay, well it's a collision so sure okay First thing I did to get a good picture as I wrote down I'm gonna assume the incoming nucleus is moving due east because that's the way that most of our collisions have worked We had something to the right. I Said collision momentum Okay with that what's moving before the collision mass one mass two or both just mass one So I crossed out mass two after the collision both are both And I drew a picture I said you know what it's gonna look something like that where that's right there is a 90-degree angle How will I add those two together draw them? Chip to tail chip to tail. Oh mass times velocity and The incoming one was due east mass times velocity This one was kind of nice because no sign law cosine law. I can actually use good old right angle trig. I used What did I use I? found theta By going shift sign, which was unusual often. We use tangent And I found this by going Pythagoras that squared minus that squared equals that squared square root Right that squared equals hypotenuse squared minus the short side squared, so this one wasn't as bad The reason initially I groaned Troy this would be an example of Because we have right angles Because the masses are identical I Think here you would find kinetic energy was concerned the amount of kinetic energy before the collision does equal the amount After the collision, this is a perfectly elastic collision. I think let me just double-check For the collision we have a half m V squared after the collision I have a half times m times 24 squared plus a half times m times 10 yep Okay, so for what it's worth if you happen to have a 90-degree angle and your masses are identical If you actually sit and do the trig you'll find oh because it's Pythagoras and so Catoa the m's cancelled and I do get well Pythagoras in disguise v1 squared equals v2 squared plus v3 squared It's actually C squared equals a squared plus v squared in disguise big deal. I Didn't do a big emphasis on perfectly elastic collisions. You do need to know what is conserved momentum. Yes or no Yes, total energy. Yes or no kinetic energy yes or no I'm taught always No, rarely only in rare specific special collisions Okay Next okay, then look up Do a bunch very quickly boom boom boom Number nine here. This is an old review. So that's why I don't have a copy for you Says what is the change in the momentum of an object of mass blah blah blah if a constant Unbalanced force of that big ax on it for that so change in momentum. What's another word for change in momentum? Impulse am I gonna use final minus initial change in momentum here? No No, so you might want your formula sheet out if you haven't already there's an equation for impulse now impulse is another word for what Miguel Change momentum, which is always final minus initial but impulse on your formula sheet change in momentum delta p is also what Zach on the formula sheet Four times change in time. How do I know without having to think about it too hard? That's the one They want me to use look at the question Do they give you a force? Do they give you a time? Fact the answer here was gonna be two point nine times four point seven. They didn't even need to give me the mass That's just to throw me off two point nine times four point seven Okay, by the way, I skipped number one number one is perfectly elastic Which means I know it's a right angle and I know the masses are identical, but it's overkill Number five an incident ball a strikes a stationary target ball B The momentum vector of the incident ball before and after the collision are shown In the above diagram whoop So there we go. I need that Which vector represents the momentum of the target ball after the collision? Let's see The momentum vector of the incident ball. So that means the first moving one. So I think I need to visualize this I Need to draw this just a little bit. So I'm actually going to close it in this program and I'm gonna Open this up in PDF annotator so I can write on this file. I think I think I think I think I think We look tired Okay So here's what we have We're envisioning some kind of a sphere coming in There's another sphere right here. So the first one bounces off this way Which way is this guy gonna bounce? Let's think about it. Which way is it gonna bounce if the first one bounces up high to the right? I'm pretty sure Gotta be a is that right? Mr. Do it. Let's find out All momentum answers Hey for me on the old provincials they used to be two hours long and the provincials were 120 marks 60 multiple choice Sorry 30 multiple choice two minutes each and 60 marks worth 60 minutes worth of written It was actually a nice little balance the physics guys had it going good And so the person who set these up who I borrowed these from mr. Christ over at SRT He would actually time himself how long it should take minimum Sorry maximum if you're pacing yourself to do it, so his you'll see next to his shouldn't take you any longer than two minutes If it does you're in trouble You're not going to finish the provincial because back then you'll need two hours not three They were you know plus year back then Number three a stationary life raft is carrying two survivors with masses of 55 and 72 kilograms respectively They dive off the raft at the same instant. Oh Before they dive, what's the momentum of the two people and the raft included? I heard it. Sorry. I heard it Yeah, zero. This is an explosion. It's a slow explosion. But when you do this question, you would go, okay? my initial momentum is zero First person second person wrapped How does zero show up in a vector triangle a triangle? It does what comes back to where it started from so I went drew a little picture here Absolute value I was using that when I first started teaching physics 12 That's the symbol for magnitude only and I was really really fussy on that I've eased up on that a little bit but for what it's worth That just means magnitude only and this was a right angle Whoo-hoo straight Pythagoras and they wanted the speed in the direction of the raft So I knew the mass once I found the momentum 387.31 I could then divide by the mass that gave me the velocity and it was Tangent I think to find the angle south of west another collision at an angle By the way, if you have a question from the review just interrupt But I'm just kind of trying to go through a bunch of stuff There's another collision at an angle number six toy car mass moving east Collides and they lock together so afterwards it'd be mad a momentum of both final means Divide by the mass of both to find the velocity This one here almost certainly. Oh Do north do east probably don't need sign law coast sign law You'll probably end up with a lovely so katoa triangle And then you'll have to find the how many degrees east of north all they want is the actual angle Number seven which vector shows the direction of the change in momentum What's changing anything? I Okay, so the change in momentum is going to be final Minus initial now they haven't given me any numbers, but I definitely know the final looks like that How do I subtract the vector? Add the opposite so normally I would go minus initial except I'm gonna add Where's the eraser here? There it is Where's the pen here? I've used this for a while There it is I'm gonna add the opposite I'm gonna add those two. How will I add those two? And you think if I'm Seeing this correctly. I think I end up with the change in momentum being straight up Which makes sense to me because I don't think the ball slowed if we ignore friction I don't think the ball slowed down horizontally at all. I think all it happened was it changes vertical direction It got pushed up so I can't I'm gonna miss it. Yeah, we've done it much like that Object a splits in two. That's an explosion. We've done it much like that Done a bunch of those another angle So here's one where we don't have angles number two a 4,000 kilogram space vehicle consists of a 2,500 kilogram main capsule on a 1,500 kilogram probe The space vehicle is traveling at 120 meters second when it's close explosion momentum Now in this case they want the speed of the main capsule after the explosion I would still start out the sum of the initial momentum Equals the sum of the final momentum But this time even though there's an explosion takes court even though there's an explosion Zach my initial momentum is not zero Before the explosion. Can you see its mass times velocity before the explosion? Oh, sorry angles ah Straight adding subtracting cross multiplying let to the left be negative into the right be positive. So momentum is mass 2,500 and 1,500 4,000 Times velocity, that's my initial momentum After the explosion, what's moving mass one mass two or both stuck together So I'll have mass one V final plus mass to the final where mass two is 1,500 and what's be final? 140 positive or negative 140 because I let to the right over here be positive. So I would replace this with 1,500 Times 140 and could you solve for the speed? You know mass one is 2,500 right so solve for the speed. What if you got a negative answer? What would that tell you which way is the main capsule moving? The left explosion was so big that it set the main capsule backwards This is actually the idea behind a booster rocket ideally what you want is this guy's momentum to be Zero or even backwards because that'll impart more impulse forwards to this guy So in a booster rocket the idea is the probe goes Taking off It is a controlled careful explosion part B says what's the magnitude the impulse It's another word for impulse Yeah, and here. I'm definitely not using force change in time. I'm gonna go final minus initial final is Probe final is mass times velocity to positive to the right minus initial This time don't look at both of them just this mass times the velocity. So it would just be 1500 Times 140 minus 1500 times 120 whatever the heck that was that's your change in both that momentum. That's your impulse How else could they change this? Oh if the explosion lasts for point zero three of a second What was the average force? acting on the probe That's where you would use the f delta t once you found this answer. Oh Here's a right to explain define impulse define impulse for me Change in momentum, and I've probably put in brackets. What do you think I put in brackets? What's changing anything I? Probably put brackets momentum final minus momentum initial and that says explain why the impulse on the probe is equal in Magnitude to the impulse on the main capsule Momentum is conserved Whatever momentum this guy gained this guy Lost that's why they said equal in magnitude, but opposite in direction So probably answered that way momentum is conserved that you know what I would probably because I have numbers here I probably prove it mathematically. I've actually crunched the numbers. I would show Since I just figured out the impulse in part B I would calculate the impulse here, and I would show that this was the same answer but negative. I Could probably do a fancy algebraic expression Proof as well, but yeah, yo This one here. I don't know. I don't remember what they wanted the provincial for this one. This was from Don't know when this one was from oh, it's on the review on yours as well Yeah, what did I say in the back? What did I say in the back? For answers because I think what I did there is I copied it if I if it's digitized I would have just cut and paste their answer from the provincial exam No, no for the proof for the explanation here So that that's that's me lifting that verbatim for the provincial exam answer key I probably if you said momentum is conserved. I Think I'd take that the only concern I would have is Do you know what the word conserved means or are you just parroting something that you memorized? Right, so I was about hedging my bets I probably just show it be easy enough to go math time velocity or to go impulse for the Capsule as well final miles initial and shows the same number but opposite magnitude Hey another one of those this one was a bit trickier because They didn't give you any velocities instead. They told you how far it traveled and how much time so you actually have to calculate this velocity first I was overkill. I thought Puck sliding do the eat to the east collides. They stick together. Oh The only twist here and the reason this is a scholarship question is instead of asking you to find the Final velocity of the two kilogram puck. What do they ask you to find instead? Change momentum. What's changing anything? Final is initial, but it would be subtracting two vectors You'd have to do trig coson. This was a 10 mark scholarship question I won't give you one this tough, but Dylan you'd have to do a 10 mark. Sorry a Triangle question like I did with Troy to first of all find the final velocity and then do a final minus Initial track vector triangle to find the change in momentum a little overkill in my mind Yes, I sent it out quite some time ago Because you were colliding things at angles Yes, which is why I sent it out after the energy test yes Where you're Causing things to bank and great up each other much like much like the pictures of many of these collisions Kind of like that you're sort of doing that No, no, no probably while you sent me a cell phone one See because you said we wrote the test before Christmas Why would I have you write a test and then decide whether or not you want to do the bonus assignment? Well, I can't find very many if any I could I would Hey, number two here explosion Okay What's the momentum right now? Boom what's the momentum afterwards still zero It's gonna be a little bit weird. It's gonna be a closed triangle I don't think this is gonna be a lovely right angle triangle because I see one at an angle There is gonna be an explosion on your test, but I'm pretty sure I kept it a lovely right angle Now because I kept it a right angle. It means I also asked the part B I'll let you think about what kind of part B's I might be able to ask you've kind of seen some hints along The way today some of the part B's that you've seen in some of these written questions something along those lines, maybe okay Ballistic pendulum this one is an old scholarship question I expect you to handle the concept of this one Justin But the reason this one is so tough is first of all They're asking you to find the speed of the bullet after the collision And they don't tell you how high this went instead They just gave you the angle and you know, this is 1.4 you have to figure out 1.4 and an angle of 22 degrees You have to figure out that height there you got to do some trig This is a much tougher question than I'm gonna give you but hopefully you understand the idea of two things colliding In a nice straight line and then with this change in height change in energy use conservation of energy number seven on The provincial and on some of my tests. I've tried to in the notes whenever possible I think we did a Baseball a bicycle rider and a car and we tried to figure out what would hurt what would injure and what would kill I think we called it pain injury and Death okay, so what would the momentum be of a car? Well momentum is what times what? Mass times velocity now city speed limit. What is city speed limit? 50 K meters per second, please 13.8. What would a good mass of a car be a hundred car way a hundred kilograms? 2,000 pounds get away from pounds kilos Look at your numbers here Leslie, let's try thousand ish So go that number mass times velocity guess of about a thousand which of those answers looks more reasonable for the momentum of a car ABC or D? I think B Right a if I divide that by the velocity 3.6. I get a car that weighs like what 15 or 20 kilos That's no I Think see if you divide that by what was the velocity? 13.6 What's a hundred thousand about it by 13? See that that's a car that weighs 10,000 kilograms. That's 10 tons the vehicles weigh 10 tons I'm not even sure those great big huge huge mining dump trucks with the tires that are higher than the ceiling way that much So it's got to be B Hey, which of those would probably be the best Representation of the momentum of a locomotive Like a full train. I think D because there I would think although not many cars weigh 10 tons I think probably two train cars would easily weigh 10 tons probably one train car might weigh close to 10 tons So if you had a train with several cars, yeah, D or higher Okay Number eight, what's this asking you to find number eight here? What's this asking you to find? number eight Here Sorry The one that I showed the entire question for as Opposed to this number eight where I didn't even bother scrolling it up all the way number eight this one here What are they asking you to find? It's good point Justin What are they asking you to find Impulse am I going to use force times change in time here? How do I know I'm not going to use f delta t? Okay, but tally at your formula sheet in front of you. There's two. There's two ways to do impulse. I'll say this again What's another word for impulse with the tally? No, no, no, no, no, no, no, no, no, no What's another word for impulse Justin change in momentum? It implies an operation Change you can't just say momentum. I'll totally mark that wrong and you'll have the wrong concept impulse is changing Which means you always need what's changing anything So one way of doing this would be to go momentum final minus momentum initial But there's also Zach can you show me your formula sheet, please? There's also an equation What's the equation? Okay, so here's my question ready for tally. How do I know they don't want me to use that equation? There's no time. What else is not here? Force and does it look like they've given me a final and an initial velocity? Yes, is there a rebound? Then you'd better let one be positive and one be negative Because I guarantee one of these answers is if you just go final minus initial and you go That times 25 minus that times 15 can't do that because you've let them both be in the same direction And it definitely says the final velocity is west and the initial velocity is east So I would probably let either to the right be positive and to the left be negative or vice versa. We all do one of those Okay, and then to figure out the direction if you let east be positive and you get a positive answer the direction is east if you let east be negative and You get a positive answer the direction is west in other words You look at what you let be positive and you look at the answer that you got if they're in the same If they're both the same sign, they're in the same direction The tally look at number seven of the first number seven this number seven Read it to yourself, please. I'm gonna use impulse here, too. Okay. Here's what I would do. I would say Change in momentum impulse is force change in time and Since they mentioned time and they're talking about force. How would I get the force by itself divide by? Time a problem. I'll do that last first. I'll figure this out. How can I figure this out? final mass times velocity minus Initial mass times velocity Opposite direction. I better let one of them be what and one of them be what? One of the positive one of the negative Then I'll go final minus initial and then I'll divide by time You'll get a negative force as an answer all that's telling you is the force is in the opposite direction of your initial velocity Which makes sense because if the ball hit the wall it had to come to a stop Which is applying a force that way and it goes this way it must apply to even bigger force this way to get it Do that way too, right? So the physics behind Just the physics behind a simple tennis ball hitting the wall right wonderful changing momentum equation Hit the paper The physics of hitting the wall with the tennis ball great example of impulse It's also nice because for a split second every linear if we ignore that it's going to drop this new gravity case It will be in our magic Even better if I do want to definitely be linear that Right, which way the ground apply a force upwards, you know the time collision implies a fair bit of force because it has to first over here to a stop changing it to zero and Then you know even more impulse to get to go back up that would be linear what would What would require a bigger change in momentum if this was flat and just Into a stop or this was all pumped up and bounce back up what requires a bigger change in momentum Well, let me ask you a different question So let's go back to Vitaly Because he's still oh But you're wearing a Russian hockey team jersey sort of Canadians almost as offensive. No more offensive Vitaly you're walking along the street in downtown Vancouver next to a high-rise and Somebody knocks a flower pot off of their window from the fourth story and it lands on your head What would do more damage if it landed on your head and came to a stop or if it landed on your head and bounced all the Way back up to the window so she could grab it again. What would hurt more? The bounce so where would your head apply a bigger impulse? Where would your head apply a bigger impulse then? The bounce because you've got to bring its momentum to a stop and give it all the momentum going up. Okay, it's Soccer players my soccer or baseball, okay Bunt Very easy on your hands along with your fingers rarely do you see a batter after a bunt get you that stinging feeling? Hit you really feel it in your hands, but you're having to apply a way bigger force way bigger impulse Okay, I've done a bit of a rant there That's energy actually That's energy oh here number 10 Two cars collide head-on and come to a complete stop immediately after the collision which of the following is correct total momentum conserved or not conserved always total energy always Kinetic energy Not always and in this case Can't be because what's the final kinetic energy? Zero what was my initial not zero otherwise you can't have a car accident Okay, anyways the answer here Done a bunch of these you can see they start to get kind of repetitive Okay, so there's either going to be two guys coming in and sticking together and moving off a nice straight line Or one guy coming in a nice straight line and then they split apart But you're gonna have one of them in a nice straight line. That's what helps you draw the vector triangle Front of a automobile is designed to crumple in a collision in order to reduce the injury to the occupants using principles of physics Tell me what the principles of physics are that help this work. Why does this improve safety Ian? Yep fact it's exactly the same as my baseball bat there is I'm sure each one of your classes. I think somebody I think I would have held a ruler and This which have almost identical masses and I would have picked somebody I would have said you're gonna get hit in the head What do you want to get hit by it's gonna be the same mass? Final velocity is gonna be zero. So it's gonna be the same change in momentum What can we do to lessen the force length of the time of impact? Troubles on and I showed you guys the smart car crash video. Yes And I went on a bit of a rant where I said it's even the passenger compartment It's actually the hypotenuse of the triangle if you look at the smart car from the side It's tilted up because they have to somehow give you a longer crumple zone And they don't have much room to work with filling in a smart car So what they did is they tilted it up like that because there's a hypotenuse longer than that There's your extra crumple zone. You have to crumple downwards a little bit. They're like nice little bit of engineering They're very clever and now you're going. Oh, that's why it looks like from the side those smart cars That's why they look like that. Yes, they designed the passenger compartment like that deliberately Uh Pardon me So I've done more from my old review Are there any more from the new review where you've been going now? Hey, I have some more questions Remember the answer key is online. So if you're stuck, it's all there. Okay Leslie I've been ignoring you. You have any questions at all or hopefully that helped a little bit I'm gonna go like that. Nope. I'm gonna go like this right click