Identify the simple machines that make up a pair of scissors\n\nand also: Why do you thin you owuld not want to reduce the friction involved in using a winding road?
209796
#1 fulcrum\n#2 you would veer off the road and lose control
491855
1 The hinge is the fulcrum of a lever. A lever requires less force to move the same weight the farther you are from the fulcrum\n\n2 a pulley\n\n3 Friction is resistance against applied force and requires additional energy to overcome thus reducing efficiency.. \n\n4 The axe is a wedge.  The wedge is also an inclined plane. An inclined plane uses more energy the steeper the angle. Sharpening the wedge reduces the angle.\n\n\nGood luck in your study of simple machines.
653564
it is a type of Machinery.
272296
1. If the population is low why use machines?\n2. In many countries election is still a dream.
74139
If you take the same lesson plan that was devised for older students and simply resolve to spend more time explaining and demonstrating to the younger kids, will that work?  I hate to think there's anything the younger ones can't do, although grant you they won't do it with the polish of the older kids.  Please tell me we are not talking about the idea that safety is a major factor in the difference; having to use blunt-end scissors, no small parts they can swallow, and all that garbage.  A major problem when I was a kid was too boring, so the idea of working on something originally designed for older kids would have thrilled me no end.
523444
I would love to have a machine that folds laundry.  \n\nI have one that washes it and one that folds it, so why not another that will fold it?
410160
Wow. Your classmate just asked this question. But here's your answer anyways...\n\nThere are a few things to keep in mind here: all of the energy in the initial system is rotational, and the initial energy is equal to the energy lost to friction. Also note that the energy is lost to friction at a constant rate.\n\n(a) The initial energy of the system is:\n\nE = (1/2) * I * w²\n\nWhere I is the moment of inertia and w is the angular velocity. The power transferred from the system due to friction is equal to the time derivative of the energy loss:\n\nP = dE/dt = I * w * a\n\nwhere a is the angular decceleration.\n\nSince the power is transferred at a constant rate and removes all of the energy from the system, we can take this as:\n\nP = -E/t (negative sign denotes power loss)\n\nCombining the power equations yields:\n\nI * w * a = -E/t\n\nSolving for a:\n\na = -E / (I * w * t)\n\nFinally, substitute the expression for E to obtain:\n\na = -I * w² / (I * w * t)\n\na = -w/(t)\n\nSubstituting the values yields:\n\na = -(150 rev/min * 2*pi rad/rev * 1/60 min/sec)/(2.2 hr * 3600 sec/hr)\n\na = -(15.71 rad/s)/(7920 s)\n\na = -.001983 rad/s²\n\n(b) The rotational behavior of the fly wheel can be modeled as simply:\n\nR(t) = -1/2*a*t² + w*t + Ri\n\nwhere R(t) is measured in radians and Ri is the initial angular displacement. Assuming that Ri = 0 (we'll measure the number of rotations from its initial position), then the flywheel will revolve:\n\nR(t) = -1/2*a*t² + w*t (radians)\n\nR(t) = (-1/2*a*t² + w*t)/(2 * pi) (revolutions)\n\nSubtituting the values:\n\nR(2.2 hr) = R(7920 s) = (-.5*.001983*(7920 s)² + (15.71 rad/s)(7920 s))/(2*pi)\n\nR = 9900 revolutions\n\n(c) The tangential component of the linear acceleration of a point on a rotating body is given as:\n\nA-tangent = a * r\n\nwhere A = linear acceleration. The angular acceleration is constant, so for all w (including w=75 rev/min), the linear acceleration will also be constant. Thus:\n\nA-tangent = (-.001983 rad/s²)(.5 m)\n\nA-tangent = -9.915 x 10^(-4) m/s²\n\nA-tangent = -0.9915 mm/s²\n\n(d) The magnitude of the net linear acceleration on the particle is composed of a tangential and a normal component. The equation is of the form:\n\nAnet = [ (A-tangent)² + (A-normal)² ]^(1/2)\n\nOr:\n\nAnet = [ (a*r)² + (v-tangent²/r)² ]^(1/2)\n\nNote that the tangential velocity is given by:\n\nv-tangent = w * r\n\nThus, the magnitude of net linear acceleration is:\n\nAnet = [ (a * r)² + (w² * r)² ]^(1/2)\n\nSubstituting the known values yields (note that for this case, the angular velocity of 75 rev/min is equal to 7.854 rad/s):\n\nAnet = [ (-.001983 * .5)² + (7.85² * .5)² ]^(1/2)\n\nAnet = 30.81 m/s²\n\nFINAL ANSWERS:\n\n(a) a = -.001983 rad/s²\n(b) R = 9900 revolutions\n(c) A-tangent = -0.9915 mm/s²\n(d) Anet = 30.81 m/s²
512161
You haven't given me any information with which to solve this problem.  How big are the blocks?  How much do the blocks weigh?  How far apart are they?  How much resistance is there when I push the first block?   How fast is the first block going when it is pushed?  Without all this I cannot figure out how much momentum is lost between the time the first block is pushed and when it hits the second block or if the second block will have enough momentum to move at all or make the third block move if it contacts it.\n\n\nBy the way, you cannot solve this without knowing how much each block weighs, how much momentum it has to begin with, how much friction there is (to reduce momentum), and how far each block has to travel before it contacts the next one.    You need to have the variables to create a formula. \n\nGeeze, don't you hate it when idiots try to act smart????
441460
I'd say the force you use is a combination of friction and gravity. The string you hold doesn't escape from your hand because of friction (think about walking on ice: you can easily slip because there's almost no friction involved between the bottom of your foot and the ground); by pulling the string, you also exert a force greater than the weight of the string (even though you might not feel it because it is very light). This is all I can think about right now, but I hope it helps
589320
It seems research on this has continued. Still sounds very preliminary though - experiments on small models or paper planes ;)  But maybe you'd like to check the links.
546175
I certainly hope you have visited the link below for visual and mathematical insights into this problem.\n\nHowever, the only materials that come to mind which lend themselves to a physical model of this transformation are:\n\n o thin-but-rigid springs or "lead" wire(s) as supports/frames\n o plastic wrap as a surface substrate\n o flexible, rubberized, quick-drying paint as a protective layer\n\nI regret that my imagination is limited with respect to this problem, but good luck with your project!
590217
You can make any simple machine having fulcrum, load and effort or u can even make a pulley.(These r very cheap and easy to make)\n\nFor ur project on universe u can get information from any encyclopedia or search in net.
94238
a compound machine would involve multiple mechanical devices.  For example a pulley connected to a lever which is connected to a gear system would be a good example.  This would be used possible to mechanically lift a load.
84162
It means that for each 2 turns on one gear, there are 3 turns on the other (though I assume you know that already).  The efficiency is related to friction loss-the greater the ratio difference, the greater the force transer and thus friction loss, so the lowest ratio difference is the one with the least friction loss.\nThere is no change in distance from the fulcrum on a see-saw unless you are talking about the very small bending of the board, and that is likely too little to overcome other small forces, such as friction, movement of the people on the seat, etc.
525043
Nice question.\n\nThe answer is.\n\nIf I was to ask your brother which road would he tell me to take to get to the good village. \n\nThe good twin would point to the road that leads to the bad village because that is where the bad twin would point. \n\nThe bad twin would point to the road that leads to the bad village because the good twin would point to the road that leads to the good village. \n\nSo you would take the opposite road that you were shown.
144425
You need a stringing machine, then it depends on what kind of machine you have. Would really need more details.\nStringing pattern can normally be figured out or taken from the previous set of strings.
596215
Dog walking.  I wish there were some teenagers in my neighborhood doing it.  We get busy and the dog could use the exercise.\n\nOtherwise, car washing, but nowadays it's not PC to run a hose over a car, hardly.