is it possible for a small car to have the same momentum as a large truck? explain.?
84112
Yes. Momentum is defined as p=mv where m is the mass and the v is velocity.  A small car would have a smaller mass than a large truck, so it would have to have a larger velocity.\n\nexample--- car has mass 5 and truck has mass 10.  car is going 20 km/h and truck is going 10 km/h.  momentum of car is 5*20=100 and momentum of truck is 10*10=100
686782
All right, I'll do my best. \n\nTwo rockets scenario: \n\nAssumptions: Both the rockets are out rigged with the same engines/propulsion systems, and have the same aerodynamic profile.\n\nThe ignition of the fuel generates a constant thrust, which translates into a constant upward force. How a force translates into motion of a body is dependent on the body's mass, more mass, slower the acceleration... less mass, more the acceleration. Thus, the heavier rocket will accelerate at a slower pace.\n\nDropping 2 bodies of different masses:\nAssumptions: Both have the same aerodynamic profiles.\n\nGravitation is not a constant force, but is a constant acceleration. Thus the rate of change of speed is fixed. The forces 'experienced' by the two masses are not the same, and the heavier one 'experiences' a larger force than the lighter one, in effect to balance out and make them drop at the same rate.\n\nKey equation (even though you didn't want one) is \nForce (F) = mass (m) x acceleration (a)\n\nIn the rocket scenario, Force is constant, so if mass goes up acceleration must go down, and vice-versa\n\nIn gravitation, Acceleration is constant, so more mass experiences a larger force.
819561
Perhaps surprisingly, the ballon will move forward (relative to the car). There are two ways to see this. One is the principle of equivalence: acceleration is like gravity, and in this artificial gravity field (directed backwards) there is a buoyancy force on the baloon (it's lighter than air). Or you could say a pressure gradient, directed forwards, has to build up inside the accelerated car (to accelerate the air), and this pressure will drive the ballon forward (the pressure is just enough to keep the air accelerating with the car, but the balloon is lighter than the air it displaces so it gains an extra acceleration).
160628
i guess you are talking about very small flies.  well there may be millions of them and you had the impression that these flies are moving at the same speed of your car.
3944
The Trolley + Child being one single system, the speed of the Centre of Mass would not vary. It would remain the same velocity V.
61716
The air inside the vehicle is moving the same speed as the vehicle. To the fly it's still air, unless a window is open, then the fly may not be able to fly normally.
757156
How about someone is run over by a car.  The owner of the car says they left it in neutral on a level parking lot, and must have forgot to set the parking brake -- the car started rolling forward before they could jump back in and stop it, and the car ran the victim over.\n\nThis can be disproven because Newton's first law (the "Law of Inertia") states that an object at rest will stay at rest until acted on by an outside force.  Since no outside force was present (the parking lot was level so no gravitational force acts to accellerate the car horizontally) and the car itself was turned off, it cannot possibly have "just started to roll by itself" -- the car owner intentionally ran the victim over.\n\nWhy would he do that?  Well I guess that will be the fun and imaginitive part of the assignment!
848599
No. The velocity of the wheel is changing as the car moves (because velocity indicates direction). So as the car moves forward, the velocity of the surface of the wheel is continuously changing.
1031072
Possible, but very difficult. \n\nIn a rear wheel drive car, I do a power drift. I shift in to a lower gear and turn the wheel simultaneously to get the wheels loose, then nail it and spin the tires to keep it moving in the direction I want.\n\nOn a front wheel drive car, that isn't possible. As soon as you let the engine take over, the front wheels are going to pull you out of the drift.\n\nYou have to use speed, momentum and brakes to your advantage when drifting in a FWD car. I really don't recommend you starting out in a FWD car - it is extremely dangerous for a beginner. Take your parent's car out or something really late at night so you don't have to worry about traffic.
549498
Depends on what kind of track you intend to use it on; straight, incline, etc. I doubt that aerodynamics will make a whole lot of difference, but you can try something aerodynamic. I've seen a number of pinewood derbies and I can't say the wedge always has the advantage. If it really made a difference nearly all would tend to win, but they don't. I tend to believe that other factors are more significant. Things like weight and friction. Make the wheels as 'slippery' as possible about the axles. Maybe you can use Teflon bushings for axle sleeves, or Teflon axles  as well as Teflon bushings unless there are restrictions of such things.\n\nAt one time I started to crunch some math to find the optimum design, but I was always derailed on some other endeavor and never finished. It's not a trivial problem actually if I remember correctly. Anyway, I'd say that the weight should be evenly distributed. So balance any added weight with the weight distribution of your body style so the mass is effectively centered width-wise and length-wise.\n\nA light car will leave the gate faster, but the heavier car will not be as affected by undulations and so on on the track, and it will tend to want to continue longer than the light car. How much heavier?........sorry.....dunno. That was part of what I wanted to find out.\n\nIf the cars start on an incline then I'd say the weight distribution should be slightly forward. If the cars are propelled on a level track, depending on the nature of the launching mechanism on the car the weight should be centered as I mentioned above. If the cars are propelled on a straight track from behind, then you'd also want a bit of excess weight slightly forward. If the car is propelled by a sling mounted on the front of the car, then the weight should be situated slightly toward the rear.\n\nThe wheels should have NO slop in them, but completely FREE to turn. The mounting of the axles should also be done just so as well. I'd say this is more in line with how you distribute the weight of the car as a whole. You don't want weight 'hanging' over beyond the outer perimeter of the wheel-base. And don't have it shifted more to one side than another. I doubt you'd do that, but I've seen some pretty crazy designs.\n\nSince you mention motors, I guess you'll be launching from a level surface. Make cavities in the car to lower the motor into to keep it from being too bulky. Selecting the motor is up to you. Find one that has a good power:weight ratio. Meaning.....high power against low weight (that's obvious ---- right?). Power it with good batteries. Don't get the cheap crap from Giant Eagle. Go to a hobby store and get good ones. Measure their voltage and make sure they are at or above their rating, and if you use more than one that they are as closely matched as you can get. Mount the motor as closely to the driven axle as possible. Avoid linkages. This will add weight...unless you have to. maybe consider driving all 4 wheels at once? BUT...they will have to be synced VERY well to pull this off, otherwise the car will fight itself and slow you down. If you need to do any wiring....use very fine gauge wire. Enough to handle the amps needed, but just barely! The finer the wire the less weight you have to haul. Ideally try and engineer the motor so you don't even need wires.\n\nIf you have to connect the motor to the axle with some kind of gearing....I'll come over and bi+ch-slap you for even thinking it......don't do that! Try and use a motor/axle assembly. Otherwise you run a terribly high risk of driving the axle out-of-center and wasting power by unnecessarily torqueing the axle. Meaning as well as turning the axle it will tend to want to rotate....no no no no no....got it?\n\nMake sure any motor you use doesn't have a wild magnetic field. Check it by seeing how many paper clips you can 'stick' to it, and how far away this
169523
I normally refrain from answering questions that have already been answered by so many people, but in this case, so many of the answers are incorrect, and it might be useful to have a single answer that clarifies what's correct and what isn't.\n\nAn object in freefall in air is subject to two forces. Gravity, which directly proportional to the mass of the object, pulls the object down. Drag acts opposite to the object's movement, and is related to the objects size, its shape, the square of its velocity, and the density of the fluid through which it's traveling. In this case, the drag force acts upwards\n\n^  drag\n|\nO  object\n|\nv  gravity\n\nThe force due to gravity is essentially constant (it increases slightly as the object gets closer to the earth, but this increase is negligible). The force due to drag is related to the size ans shape, which is constant for rigid bodies, and to the speed, which is increasing initally.\n\nThe objects will accelerate until the forces are equal. This occurs at terminal velocity. I would estimate this to be approximately 100 mph. It would take more than 300 ft to reach this speed.\n\nIn a vacuum, there is no drag force, so the acceleration due to gravity (about 9.8m/s^2 near the earth's surface) would continue to accelerate the objects until another force acted on them (e.g. hitting the ground).\n\nSimilarly sized, shaped, and weighted objects such as an egg and an orange could be expected to fall at almost the same rate.\n\nOne final note has to do with a term I used earlier. Neither an orange, nor and egg is really a "rigid object". The egg especially might experience some degree of sloshing inside which could affect its motion. This is why tanker trucks have compartments. I'm not sure if you'd notice this effect, but if you hard boil one egg, you could perform an experiment yourself.\n\nThe bottom line is that you really shouldn't notice any difference in the way the orange or the egg falls.
904699
No.\nThere are many places in the U.S. where it ""appears"" that a car will coast ""uphill"". All of them are based on optical illusions.\n\nAnd No, there is NOT a possibility for everything.
924224
No.  The design of the vehicle does not matter, it is the old e=mc^2.\n\nAs you accelerate, your vehicle gains mass, until, as you get closer to the speed of light, the mass gain approaches infinity, and it then takes an infinitely powerful push to overcome this infinite resistance.\n\nIn the case of the nested doll ships, if we use the external (larger ships), to begin the journey, you would find yourself in the strange position of continually needing greater power from ever smaller engines.
609692
No. All motion is "Forward". Right down to the tiniest Particle. It can be pushed but not pulled. No matter the direction.
1121436
let's see. The car in on large piston, right?\n\nso the pressure increases by 90/250 units.\n\nthe additional weight needed to compensate from from the small piston side is (90/250)*10=90/25 kg\n\nthis weight must be provided by a weight of oil going up in the small piston, it's volume being 90/25/560 m3, \n\nso the large piston must go down to provide this volume by\n90/25/560/.025=0.2571 m  (slightly under a foot)\n(m2 = 10,000cm2, so 250cm2=0.025m2)\n\nSo I guess 0.2571 m  is the answer. \nDo not remember any of this physics, but this seems to be the only way to link the numbers.\nLemme know if it is right :)
354103
Think of a car traveling at 90 mph up a ramp. When it gets to the end of the ramp all four wheels leave the ground and the whole car continues upward. Is gravity broken? No, it's just that the velocity of the car upward has more force than gravity trying to pull it down. Of course it will pull it down as soon as the upward momentum decreases enough.\n\nAnother example. The Shuttle orbits around Earth even though gravity is still there and as strong as ever. Again there are two forces at work on the Shuttle -- gravity is pulling downward while at the same time the Shuttle's speed is trying to hurl it off into space. The two forces aren't cancelled or "broken," they're just balanced so that neither completely gains control of the Shuttle.
1054432
I don't remember very well I but I red somwhere about a F1 car beating a F16 fighter on a 2km distance.\n\nLet's take an example: \nRoughly a 747 weight about 400tons and has 4 engines of 25tones of thrust. This would lead to a maximum acceleration of 0.25Gs at take off. I'm sure a fast car can do better than that