If a car is travelling at 70mph and a fly is flying inside the car...at what speed the fly is actually traveling?
128407
Speed is always relative to something else.\n\nSo, relative to the car, the fly is going at quite a low speed as it buzzes around inside.\n\nRelative to the road, the fly is going at just over or just under 70mph, depending on which direction it is flying within the car.\n\nRelative to the sun, the fly is moving at thousands of miles per hour as it rotates once around the sun every year, just like the rest of us.
333168
Let's consider the case when the Car is right in front.\n\nAt that instance, the car is travelling tangentially to a circle of radius 132ft, where the Camera is the centre of the circle.\n\nCircumference of the Circle = 2*(pi)*R\n= 2 * pi * 132 = 264*(pi) ft.\n\nTime taken to travel the entire circumference by the car\nT = circumference/velocity = 264*(pi)/264 = pi seconds\n\nHence the car would require pi s to cover 360 degrees of the circle.360 degrees = 2(pi) radians.\n\nW = angular velocity = 2(pi)/pi = 2 radians/sec.\n\ncan't help about half a sec later now
184132
HAHAHAHA You all forgot about our little friend called drag! Inside or out the ball has a drag force acting on it by the surrounding air. Like stated before the air in the car is moving with you, and the car, and the ball all the same and the drag force on the ball at this point is negligible. This is not the effect of a vacume, a vacume is the absence of air. is it possible for there to be no air in the car? NO, Sooo.. outside on a bike or where ever, you are traveling at a speed where the balls light weight will be significantly affected by this drag force and it will cause it to slow down as you throw it up and while you keep riding on un affected by the static(motionless) air, your ball only has one force acting on it, air drag causing it to slow behind you.   test this by throwing a variety of same shaped objects while riding and you will see that the one with the most density will keep up the best. try a marble V.S. a ping pong ball.  then do it in the car
366261
SRY!! Matt is going to a basketball game out of town. If he could travel 75mph, He would arrive one hour early. If he could travel 45mph he arrives one hour too Late. How far is Matt's trip\n\ndis=75*(time-1)\ndis=45*(time+1)\n\nthen\ndis= 225mile,    time=4hour
197414
That is because the fly IS moving at the speed at which the vehicle is moving. By the way, it DOES NOT hover at the same place. Suppose the fly is a little fast than the car , then it appears to the fly that the wind-shield is moving towards it and it then adjusts it's speed to remain in the same place( if it chooses to). In the same way in all other cases, it modifies it's speed.\n Someone above pointed to inertia. Remember inertia only acts if the fly or any other object is in contact with the moving object. Otherwise it does'nt come into picture.
341641
V=Vo - a*t\nD=Vo*t-a*t^2/2\nWhen braking without slipping,\nF=m*a\nm*g*0.642 = m*a\na=0.642*9.81=6.3 m/sec^2\nconvert mph to m/sec we get Vo= 17.8 m/sec\nThen,  17.8 = 6.3 * t  hence t =17.8/6.3=2.83 sec\nD=17.8*2.83 - 6.3*2.83^2 /2 =50.37-25.23=25.14 m
114568
Assuming their speeds never changed, if after 3 hours they were 2340 km appart that means the distance between them grew by 780km every hour. (2340:3=780) After the first hour they were 780km appart after the second 1560km after the third 2340. (since the distance they cover each hour doesnt change)\nIf they were traveling at same speed that would mean 780km/h:2  they would travel at 390km/h each. They have a 80km/h speed difference though, therefor one is flying 40km/h below the average speed of the two, the other 40km/h above their average speed. 390km/h-40km/h=350km/h and 390km/h+40km/h=430km/h (you reduce the speed of one plane by half the difference and increase the speed of the other by half the difference so the total difference is the correct one. If you only reduced the slower plane's speed by the complete difference, then the combined speed of the two planes wouldn't be enough to cover the distance you want)\n\nverifying results: 350km/h+430km/h=780km/h and 780km/h x 3h = 2340km\n\nTherefor plane one has a speed of 350km/h and plane two has a speed of 430km/h\n\n...hope this helps (and hope this is correct :P)\nOh and don't just copy it down. These exercises are supposed to help you think in certain ways so make sure you can solve the next one yourself.
444164
You need to find out what uniform acceleration will cause the car to travel 40m in 3 seconds from rest. Then you can use force=mass*acceleration to work out what net force is needed to get that acceleration. \n\nWhy not draw a velocity time diagram? the velocity increases linearly from 0 to V in 3 seconds and you need the area under this straight line to = 40 so V will be 80/3 m/sec\nand the slope of the line is the uniform acceleration = 80/9 m/sec/sec. Now work out your f.
412423
Assuming that this drag factor gives the maximum fraction of g that the car could decelerate at then using a=32*.75 gives a=24ft/s/s and the initial velocity would have been roughly sqrt(2*24*71) ft/s (say 58.5ft/s)\n5280ft in a mile and 3600 seconds in an hour means mph=ft/s*3600/5280 , about 40mph.\nAt 25mph ~ about 36.6ft/s the same decelleration would have stopped the car in 36.6^2/2/24 feet so yes the pedestrian would have been fine. all the above used v^2=u^2+2as\nwith a=acceleration in ft/s/s (-ve as acting in the opposite direction to u), s in feet, v=final velocity = 0 and u=initial velocity in ft/s.
478930
a. 1.10 MJ\n\nEnergy = mass * acceleration * distance = m * a * s\n\nm = 1600 kg\nAssume that the car is accelerating at 1 m/s^2 =>  a = 1\n\nIt would take 25 seconds for a car accelerating at 1 m/s^2 to go from 15 m/s to 40 m/s.\n\nThe average velocity during the acceleration is (15 + 40)/2 = 27.5 m/s.\n\nThe distance, s, is 27.5 m/s * 25 seconds = 687.5 m\n\nm*s*a = 1600 kg * 1 m/s^2 * 687.5 m = 1.1 e6 J = 1.1 MJ\n\nIf you assume another acceleration (let's say 5 m/s^2) you will get the same because the same amount of work is being done.
43169
Fnet= MA so you acceleration is 36km/h, so convert that to m/s, which is 10 m/s. To get acceleration, we know that the car started out at 18km/s, which is 5m/s. So the acceleartion = Change of velocity/Change of time. So that comes out 1 m/s/s. So there is 1000 Newtons on the car. The other guy's answer is wrong. I'm an engineering major. The standard Units in science is MKS, meters kilograms and seconds
494320
The change in momentum of the automobile is equal to the impulse of the applied force.\n\nInitial momentum = mv = 1200*50 = 60000 km-kg/h\nFinal momentum = 0\n\nWe need to convert the 60000 km-kg/h to useful units\n\n60000 km-kg/h * 1000 m/km / 3600 sec/h = 16667 m-kg/sec\n\nImpulse = force * time = F*0.14 sec\n\nSo F*0.14 = 16667\n\nForce F = 16667/0.14 = -120 KNewtons\n\nNote that the applied force is against the original direction of motion, so the force is negative...
191133
you multiply the # of KM by 0.6.\n\nex: If a car is traveling at 80 KM/hr, how fast is the car traveling in miles?\n\n80 km X 0.6 = 48 miles/hour.
433053
wish I could solve em for you but ill try and help still.\n\n1) The acceleration should be the derivative of the equation for the car's velocity.  The original distance/time equation would be the anti-derivative of the velocity.  \n\n2 The equation to find out how long it will take to get there is h+ax-16x^2 in feet.  (a is the original speed and x is number of seconds and h can be the height of the building.)\n\nHope this helps
62906
The shape of the car is not the only factor in how fast it goes. However it is one of the most important factors in driving fast and doing it with some relative safety. The word you are looking for is aerodynamics. Aerodynamics is how well air moves over and around the car. Aerodynamics also holds the car to the ground creating what is called down force. Cars can be shaped to give more or less down force to any givin side of a car. The Saleen S7 is said to be able to be drive upside down at 160 mph and still have all 4 wheels on the ceiling.
246214
You and fly are in the moving car, so both of you are at rest relative to each other. So when the fly goes from back seat to front or from front to back, it is faster than you, bacause both of you were at rest within the car.\n\nFor example, we all are in the moving earth, so all our speed is relative to earth, we do not take into consideration the earth's speed. I hope I am able to make it clear.
17012
einstein's theory of relativity.  in the frame of reference of the car, you are stationary, the fly is stationary, and everything else in the car or moving with the car is stationary. this is why if you are in a car and drop a book onto the seat, it goes straight down, not toward the back. it is going at the same speed as the car and therefore is still relative to the car. there is no force acting on it to make it behave otherwise.  that's why you don't feel anything in a car unless you're accelerating or decelerating. so you feel like you're pushed forward when the car is coming to a sudden stop. because then there's a force stopping the car, and therefore you, so you feel it. in this case, the fly would also go flying(no pun intended) to the front of the car.\n\nif this is still unclear, think of the earth. the earth is rotating with a speed of over 1000 m/s, but you don't feel it. that's because you're moving at that same speed, you're stationary relative to the earth so you feel stationary because your frame of reference is the earth.