full answers of possible factors affecting frictional forces?
492055
Rolling friction : http://webphysics.davidson.edu/faculty/dmb/PY430/Friction/rolling.html\n\nSliding friction: http://www.mtsu.edu/~phys2010/Lectures/Part_2__L6_-_L11/Lecture_10/Friction/friction.html
883840
The force due to friction (whether static or kinetic) is dependent on the appropriate coefficient of friction (static or kinetic), between the materials, and the mass of the object (which defines the NORMAL force between the two surfaces). \n\nBy the way, the coefficient of static friction is ALWAYS greater than for kinetic friction.\n \nNow, no matter what the surface area, the normal force will remain the same, since the mass remains the same. In other words, no matter what side you put the block on, the force due to static friction and the force due to kinetic friction will not change.\n\nHope this helps!
153998
If you examined almost any surface under very high magnification, what looked smooth to the naked eye would look like endless mountain ranges in all directions.  If you then place two such surfaces together using weight or another force to join them and tried to move one surface relative to the other, the opposing "mountains" would have to slide up and over each other or even break (shear) the mountain tops.  The resulting resistance to motion is called friction.  When mountain tops are sheared, the energy forcing the motion is converted to extremely high local heat at the molecular level as bonds between millions of atoms and molecules are broken.  Friction causes heat and can quickly destroy an engine bearing that loses its lubrication.\n\nThe high heat of friction can actually cause a lubricant (oil, etc.) to break down and bond (as olifins) to the metal parts making smoother surfaces, especially when the parts are held apart by a film of circulation oil that carries away excess heat to a heat exchanger.  Grease (which is often a mixture of soap and oil) is thicker than oil and can fill the microscopic mountain valleys so that the parts slide on opposing layers of grease reducing friction and heat.\n\nWhen you push on a heavy crate, you must apply enough force to overcome the static friction (sometimes called stiction) and start the crate moving.  Continued motion creates dynamic friction generating a constant supply of heat.\n\nIf you place any object on a board and lift one end, all materials (combinations of board (incline) and object (load) will slide before the board reaches an angle of 45 degrees.  The higher the board angle, the higher the coeficient of friction.  This method can be used to calculate the coefficients of friction for various combinations of materials (board and load).  Ice on teflon has perhaps the least coefficient of friction and is very slippery.  The objects and board should not serve as cogs or act as adhesives to get valid results.\n\nFamily friction (strife) is the only kind of frictioon that can be reduced by flowers or a hug and a kiss.  That may cover most of the other types of friction, right?
919106
They all involve friction, but I think you mean which has the most force due to friction, right? :-&#92;  If so, I believe the answer is that they are all the same.\n\nIn simple situations, the frictional force created by sliding two surfaces against eachother is given by:\n\nf = u * N\n\nWhere u (mu) is the frictional coefficient (an experimentally-determined constant) and N is the normal force, which is mg (mass times accelleration of gravity) if the surface isn't tilted.\n\nSo, assuming the frictional coefficient is the same for all sides of the book, there is no reason why changing the sides would make a difference.
376523
it depends on the angle of ur effort. lets say there u are trying to move a cart. if u push the way u will push ur mower, one component of ur force will be downwards, thus effectively pushing the cart down and thus increasing the frictional force . but if u pull the cart this force will not be downwards but upwards and hence the frictional force will be reduced. so its better to pull.
905447
The net force is 0 Newtons. The force of friction is 100N.\n\nThe key here is that\n1. No acceleration.\n2. Horizontal force only.\n\nThis means that the forces are balanced in the horizontal direction. The object isn't accelerating so net F = ma = 0.
136353
If you consider a model in which both surfaces which cause friction have crusts and troughs, and their interlocking causes the frictional resistance, then it is explained as follows.\n\nThe lubricant molecules fill up the troughs in both surfaces and make them more or less even, and hence there is less interlocking among the two surfaces, and so less friction.
734736
first one is easy\n\nfirst find the normal force\n\nFf (friction) = Fn(normal force ) (.35)\n0(motionless ) = Fn .35\nFn = -.35\n\nfrom there its easy\n\nFn = mgsin(theta)\n\nsolve for theta\n\n-.35 = (200)(9.8) sin(theta)\n\nand solve it ur self\n\nsecond one, tell us wat u want us to find and we can tell u, but here are the things u can find, ill give u the formulas\n\nacceleration = 0 (constant speed)\ntheta = 15 degrees\nvelocity = constant\n\nthats pretty much it, from what u gave me
834102
1)  I'm not entirely sure.  It may just be the preference of that publisher, or just that the quantities being compared were not measured more accurately than to two places.\n\n2)  The coeffecient of friction is basically a measure of how well two surfaces slide against one another.  Pressing down simply increases the force, it does not necessarily change the structure of the surfaces in contact.\n\n3)  The coefficient of friction has no units because it is a ratio.  If you were to write out the units being compared in a fraction, say 2 Newtons / 4 Newtons, the units would cancel out when divided.
897942
You should only ask one question at a time.\n\nI will answer the first:\n\nConsider the forces on the box:\n\nGravity vertically downward\nfriction pulling backwards\nThe force of gravity parallel to the ramp \nminus the force of friction\n=m*a=m*1.22\nso\nm*sin(34)*g-f=m*1.22\nfriction can be expressed as\nf=m*u*cos(34)*g\nnote that mass divides out\nsin(34)*g-u*cos(34)*g=1.22\n\nu=.52\n\nj
379528
Friction and erosion.
783086
Gravity is pulling down on the object, air is resisting it (pushing up, if you will) and causing friction, and if there's any wind it's pushing sideways on the object. I doubt you'd have wind in your problem, though. Wind is complicated :)
35148
Frictional force, F = u*m*g\nHere, F = 300 N, u = ?, m = 80 kg, g = 10 m/s/s (assume)\nTherefore, 300 = u*80*10\n=> u = 3/8
918757
because the moistness causes friction
333756
Friction causes motion. The greater the coeeficient of friction is, the more force is being applied. With enough friction, you could tear skin, or even your whole arm! you can reduce friction by not puttin anything on it. e.g., shirts, socks, clothing etc..
924331
a) 1. friction coefficient\n2. whether the bead is tilted as a whole or some portion of it. if a portion then you need to know mass distribution of patient and where the bent in the bead is.\n\nb) assuming the bead is tilted as whole then F_friction=mu*mg*cos(32deg) ,ie a projection of force due to gravity onto the normal axis.\nthe friction force is balanced by the projection of force of gravity to surface: mg*sin(32deg),\nequate the two, then you get mu=tan(32deg)=0.625
543978
Frictional force, f = uR\n\nwhere u - frictional constant\n(it is actually "miu", but I can't typr it out.)\n\nand R - the normal/reaction force (which is the reaction caused by the action of the object's weight.)