a jet airplane travelling from london to rome covers 200km in 15min.\nhalfway through the journey the pilot experiences engine problems and has to reduce the amount of thrust produced by them.\nas he reduces the thrust how does the foward force now compare with the backward force?
210414
As the plane's engines provide thrust, there is a certain amount of force countering it in the form of drag. So if the thrust from the engines were to drop off, the drag force would be greater than the forward force. (Eventually, the drag force will also be reduced so that the two opposing forces will be in balance again.) Because of this, the plane will immediately start to decelerate.
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.
492206
Recoil, in common everyday language, is considered the backward kick or force produced by a gun when it is fired. In more precise scientific terms, this force is equal to the derivative of the backward momentum resulting when a gun is fired.\n\nThe backward momentum is equal to the mass of the gun times its reverse velocity. This backward momentum is equal to the sums of the two forward momentums by the law of conservation of momentum and is due to and equal to the projectile's mass times its velocity added to the mass of the escaping gases, burnt propellant, unburnt propellant, and other gases, times their respective velocities. \n\nFor your case, we don't know enough information about the gases and other by-products of the firing. However, if we assume they are negligable, we can focus on the bullets.\n\nConservation of momentum:\nMh * vh1 = Mh * vh2 + Mb * vb\n\nwhere;\nMh is the mass of the helicopter\nvh1 is the initial velocity of the helicopter\nvh2 is the velocity of the helicopter after the firing\nMb is the mass of the bullets\nvb is the velocity of the bullets\n\nDepending on the accuracy of the answer you want, you may want to consider that the mass of the helicopter will change as the bullets leave the gun.\nMh * vh1 = (Mh - Mb) * vh2 + Mb * vb\nhowever, you don't have enough information to solve it in this case. You would need to know the velocity of the helicopter after the firing (vh2). Don't worry about it, I am probably just confusing you.\n\nBack to the question:\nMh * vh1 = Mh * vh2 + Mb * vb\n\nMh * vh1 - Mh * vh2 = Mb * vb\n\nMh * (vh1 -  vh2) = Mb * vb\n\n(vh1 -  vh2) = Mb * vb / Mh
477803
a)\nRate = Distance/time = (24000 ft)/(20 min) = 1200 ft/min\n\nb)\nTo write A(t), you know that the max. value is 24000 and the plane descends at a constant, linear rate of 1200 ft/min.  Thus, you can write a linear equation of this model:\n\nA(t) = 24000 - 1200t, where t = time (in minutes)\n\nPlugging in 0 (at initial time), the height is 24000 feet, which matches the fact in the problem.\n\nc)\nThough linear functions have infinite ranges and domains, this problem is limited to the realism of the problem.  The range is only limited from the maximium value (24000 ft) to the ground (0 ft).  You can't have a negative value for altitude because that would not make sense in the problem.  The domain is limited to the time in air (20 min).  You can't have a negative time and time after 20 min is irrelevant because the plane has already landed.  Summarizing:\n\nDomain: 0 <= t <= 20\nRange: 0 <= A(t) <= 24000\n\n--------\n\nHope this helps
435666
The total Ke is the same as the work done by both the jets and the catapult.  Since the jets did \n2.1*10^5 * 87 = 18,270,000J and the total Ke is 4.5*10^7J then the catapult must have done\n4.5*10^7 - 1.827*10^7 = 2.673*10^7 Joules of work on the aircraft.\n\n\nDoug
500541
F(net) = m x a\n\nF (net) = F (forward) - F(air friction)\n\nso  F(air friction)  = F (net) - F(forward)\n\nMass is given 20 kg\n \nnet acceleration given 2.0  m/s^2\n\n\nSolve for the Net Force, subtract the forward force, the difference is the force due to air friction.
383609
The jet is travelling WITH the circular rotation of the earth at an angle that iallows it's relitive "Ground speed" to be 5mph. Although the aircraft has an "airspeed" in excess of the sound barrier, "ground speed" is the measuring speed in this instance.
364381
Yes\nIn the northern hemisphere propellers must rotate clockwise and in the southern hemisphere counter clockwise, reversing the direction causes the plane to fly backwards.\n\nThis is known as Coriolis force.\n\nIf a plane travelled from Wellington New Zealand to London (roughly opposite points of the globe) a passenger will notice that their money is worth less, conversely if a passenger travelled from London to Wellington they would notice their money is worth more, this is due to the principle of the conservation of energy.
48752
I'm not sure I understand the question.\n\nBut if the spaceship is travelling at a certain speed - relative to the Earth - then so is the astronaut. So when he gets out of the spaceship his/her speed *relative to the spaceship* is about zero. They travel together, in other words.\n\nIf there were friction things would be different. That is why if you try to walk on the wing of a 747 you will not remain travelling with the plane for very long.
19029
Sorry, but with the time you spent typing these questions you could of looked them up in your physics book or googled them.  Sometimes getting others to do your leg work isn't always the best answer to a problem.  Good Luck in your new class!
115087
Solution: According to Sunkist's law of conversion - as you reached terminal velocity and the time portal appeared - Chiquita's banana-form entropy would come into play around France. \n\nAnswer: 2
589970
I have flown from Anchorage Alaska to Boston Mass a couple of times, and the flight time from one direction to the next does not change.  The earth is spinning, but so is the air that surrounds it.  If you are flying across the northern half of the country its faster to fly east because of the jet stream
126232
When a vehicle accelerates forward, there is inertia that holds us back until we compensate for it.  The air in the bus also moves forward because it is contained and restrained by the walls, roof, floor, and windows.  The air that the bug is flying in is also first compressed in a backward motion and then stabilized.  Its a good thing, else when the bus moved forward if all the air pooled on the back window then the driver and everyone up front couldn't breathe.  Just as that air exerts an outward pressure upon itself and everything else (if there were no pressure, there would be no wind resistance) that keeps it from collapsing at the back of the bus when it moves forward, the bug continues flying by the same aerodynamics that permits it to fly in the first place.
626140
We are fairly close.  The current generation of jets are what is called fly by wire.  What this means is that computers deliver all the commands that make the aircraft fly.  Airbus, for example, does not use the conventional aircraft steering yoke (steering wheel) but uses a joystick beside the pilot.  Both Boeing (an American aircraft manufacturer) and Airbus (located in Europe) say their new aircraft can indeed take off, fly to a destination, and land the aircraft by inputting the origin and destination locations.  This is as close as we are presently to flying a plane by "pushing a button".\n\nHope this helps and isn't too complicated.  Maybe some day I will fly on an aircraft of his design!
374129
a) it is always same speed.\nb) Vf=at+Vi\nVf= -8m/s (because it is going downward)\nvi= 8m8s\na= -9.8m/s^2\n\n-8m/s=(-9.8m/s^2)t+8m/s\n-16m/s=(-9.8m/s^2)t\nt=1.63 s
459691
The braking force was enough to dissipate the kinetic energy.\n\nForce x distance = work = kinetic energy\n\nma x 160 = mv^2/2 , notice that m cancels out\n\n160a = v^2/2, solve for v...
193150
A fly uses the air around it to fly. A fly flaps it wings to push the air and the air in return pushes the fly(NEWTON's third law).\nSo in a plane the air inside the plane moves at the same speed as the plane itself. So when the fly uses this fast moving air the fly also moves fast.