a.sliding\nb isnt the answer cause it is dumb\nc.rolling\nd.fluid
132671
Water and impurities in the water cause friction.
37042
I think the hardest question ever asked was asked by a scientist.  This was the question, and it literally drove him insane thinking about it:  Two large metallic orbs are traveling towards each other on a collision course.  Both are indestructable, and nothing can divert them from their path in any way.  They can never stop moving on their path for any reason.  What would happen when they collide?  Neither can be moved from the path that they are traveling, they cannot be destroyed, and they can never stop moving.
346742
water\nEdit:i think@_@ im stupid. wheat!^_^
128110
a) cube...final answer
27115
Initially, the ball is pushed, it slides. There is no rotation, as stated in the problem/question. This means there is no rotation at all. That all the velocity is translational.\n\nFor this scenario think of the ball as a solid block that has been pushed and it sliding across the floor.\n\nAs stared, at some time (t1) the ball begins to roll.\n\nAt this time, the ball's motion is both rotational as well as translational. In other words, it rolls as well as moving forward. This motion is what takes place at the *contact point* of the ball to the floor.\n\nIf the ball rolls, it is not slipping.\n\nIndeed, the friction causes the linear motion to decrease, and eventually stop the ball.\n\nThe rotational motion of the ball is also undergoing friction. A rolling sphere's motion is very subtle and often misunderstood. By virtue of the ball's mass there is a very tiny (tiny is relative to the mass and material) flat spot between the ball and the surface upon which it rolls, whereby a small torque gives rise to a resistance of the motion. This is why a rolling sphere slows. But.....since there is friction, the velocity of translation, is related to that of rotation by the following:\n\nv^2 = 2gh/(1 + I/Mr^2)\n\nWhere M is the mass of the ball and "r" its radius, I its moment of inertia. This is common notation. If there is no rotation, then the moment of inertia term drops out (I = 0) and you are left with a velocity which is strictly that of a translating body......kind of like free-fall.\n\nIf the ball is given one initial push to give it the initial velocity Vo, then unless there is some other forcing function at work, friction will act to decrease the motion of the ball, and all said velocities thereof. None of the velocities will increase.\n\nIf you know of a situation where such a case can exist where the ball increases velocity without doing anything to it.....make sure you mention my name when you pick up the your Nobel Prize.\n\n:)
13001
It is 'B'. But I don't understand why you put up this question under 'Physics'!
237997
Friction, Heat generated to name 2 reasons.
500476
1D\n2D (acceleration can be negative in which case you mihgt call it deceleration)\n3B
128049
Well you don't say what kind of information you are looking for, but the only difference between a ball rolling down the half pipe and a slippery object sliding down the same half pipe is that some of the energy goes into the rotation of the ball as it rolls down the slope so it will accelerate a little more slowly than the sliding object would. For example bobsled sliding down an icy track will get to the bottom a little faster than a bowling ball rolling down the same track when it is dry in the summer.
243306
a) the ground is counteracting the force of gravity, so the rocket is at rest, no other outside forc is acting upon it.\nb) becuase force is applied to the rocket.\nc) becuase of the force of gravity (and friction from air)\nd) if there were no gravity or friction from air
53165
The answer is obviously (A). The bar may shrink a little, but it can't disappear completely, as the options B, C and D imply!!\nHence, by process of elimination, the answer is (A). :-)
166268
The answer is Pressure\n\n10 pts plz! im only level 1!
577029
You probably mean "identify the frictional force acting on this object." Since we don't know what the object is, we can't really help you...
545686
Batton Twirling\n\nTiddlywinks\n\nNose picking\n\nNot necessarily in that order!!!
188513
A. FORWARD SHIFT  \n\nB. REMAIN THE SAME\n\nC. REMAIN THE SAME\n\nD. FORWARD SHIFT\n\nE. REVERSE SHIFT\n\nF. FORWARD SHIFT\n\nG. REVERSE SHIFT
449637
the correct answer is not listed ( 32 would be correct if box 2 did not move ) \n\nsince the friction of the surface is not given the correct answer is unknown - it would be the amount of force required to overcome the friction OF THE SECOND BOX ONLY ( you said BETWEEN the boxes and when in motion force is proportional to resistance )\n\nor you did not phrase the ? properly ( likely )
156359
hard questions\n1 = friction\n2 = flow\n3 = path\n4 = amps (best i can do sorry)\ni think...