From what I read on the internet I found that increase in surface area that is in contact is offset by the reduction in pressure. What exactly does it mean?
This is what I understood from the it (but my understanding might be absurd :-p): does reduction in pressure mean that the "hills" or...
Hey all,
I was recently searching for kinetic friction coefficients, and I noticed that for a reason which is unknown to me, some materials had not been appointed such coefficient. The specific kinetic friction coefficient that I'm looking for is aluminum on greasy/lubricated cast iron. Any type...
I think I have solved the first three, and only really need help on question four.
For number one, I used Fc = (Mv^2)/R and just rearranged it for velocity so I ended up with v = sqrt(ac * R)
For number 2 I used Ff = Fn*mu and got Mg*mu = Ff
For number 3 I used w = Ff*d and got w = -Mg*mu*l...
lets say a hammer of 0.5kg strikes a nail at 10m/s. The nail penetrates into the wood by 1cm. The reason why the nail stops is because friction has eventually overcome the nails momentum.
The retardation of the nail can be worked out, but Can you calculate the force that stops the nail if you...
I used work energy theorem between initial top point and point x along the incline(downwards) i got the expression of v then diffrentiated it to get a maxima but it gives me a wrong ans which is 10/6 but the actual ans is 10/3 please tell me what i did wrong
Hello,
I am having a headache to try understand a possibly simple real-world problem: efficiency (as in number of strokes/cumulative length needed) to saw steel, assuming a constant sawing length per stroke and a known steel sectional area.
I began to think about the few assumptions I assume...
1. For the car to apply brakes, we have ##v^2=2ar⇒a=\frac{v^2}{2r}=μg\;\;[ma=μmg]⇒v=\sqrt{2μgr} ##
2. For the car to go in a circle ##\frac{mv^2}{r}=μmg\Rightarrow v=\sqrt{\mu gr}##.
We find from above that the maximum velocity ##v## possible to avoid a collision is ##\sqrt{2}## times as much...
(a) Ridiculously simple though it looks, I can't see how the string will be tight. One of the two has to be true.
(1) The static friction ##f_S = mg \sin\theta = 25\times 10\times \sin 30^{\circ} = 122.5\; \text{N} ##. The maximum static friction ##f_S = \mu mg \cos \theta = 0.6\times 25\times...
The figure is shown above. In order to facilitate solution, I need to separate each block and draw the free-body diagram (FBD) with all the forces acting on it.
1. Let me start with the lowest block. Let me put its FBD as shown below.
For forces in the vertical direction, ##N_3 = N_2 + m_3 g...
Well, I'm having trouble with the free body diagrams. For ##A## we have
##y)## weight, normal force, contact force with ##B##, ##F . sin(36.8°)##. And the acceleration is ##0## because we want to calculate the maximun force before moving.
##\Sigma \vec F = m . a_y##
##\vec N_A + \vec F ...
I know the ans comes out to be mgsintheeta/3 by using f=ma and the torque eqn but my question is as stated in the question the cylinder is in pure rolling hence friction should only try to oppose mgsintheeta so that the accelration does not change hence v remains equal to rw so why is the ans...
A long horizontal rod has a bead which can slide along its length and is initially placed at a distance ## L ## from one end A of the rod.The rod starts from rest in angular motion about A with a constant angular acceleration ##\alpha## .If the coefficient of friction between the rod and the...
1). I calculated maximum safe velocity using the equation -
V(max)=√200x10x0.2
=20m/s
So the speed at which car is traveling is greater than the safe speed.. So the car should skid. So why 4th option is not correct ?
Hi.
Processes involving a friction force whose direction somehow depends on the direction of the velocity, such as ##\vec{F}=-\mu\cdot\vec{v}##, aren't symmetric with respect to time reversal. If you play it backwards, this force would be accelerating.
On the other hand, friction dissipates...
This is a deep well & the dimensions of the bottom chamber is 5x1x5ft which holds 187 gallons. The pump is located in this chamber with a piston/plunger only going up to the top of this chamber at 5ft.
The pump pushes 187 gallons into a 6inch diameter pipe which is 1000ft long = 1,470 gallons...
A man tries to climb up a rope with acceleration, ## a ##. What does he actually do to climb up?
My Interpretation
Let the man pull the rope at point A. So the Point A will pull the man with Tension, ## T ##. But at the same time the man is holding the rope, so there will be some normal...
Given that a body is moving with a constant velocity on a rough surface. Is it possible to say that if the force (which keeps the body moving with a constant velocity) is withdrawn then the rate at which it will decelerate = limiting frictional force / mass of the body? {Force = m * a}.
Thank you.
Here's the given F-t graph
My Attempt.....
Fsmax=10N & Fk= 5N
I made equatiom F=5t-5 ( by seeing Force force and Counteracting kinetic friction)
reduced the formula to a=(5t-t)/2 wrote a=dv/dt and solved it but got wrong answer.
I've witnessed 1st-hand with my own eyeballs this guy riding an S-shaped path through chicane at Thunderhill East+West 5-mile combined course with front-wheel IN THE AIR! I believe bike is a Yamaha TZ250, 100-120bhp and 200-lbs weight.
I conducted an experiment to document behavior of single...
It seems to me that this transition implies going from kinetic friction to static friction. The kinetic friction would apply a torque that would slow down the object's angular velocity, but I'm not sure how this connects to the object suddenly transitioning into rotating without slipping.
Summary: Relation between deformed foil and friction force
Good morning everyone,
i have a small leaf or steel that is bent from one side by a Pressure of many bars.
in front of the leaf there's a rotating disk, separated by the leaf by a small gap.
this leaf, as it deforms, wins the gaps and...
I feel like it would go on the side of the energy the object has where it starts - an object dropped off a cliff would be modeled U - W = K but an object thrown upwards from ground level would be
K - W = U. I am not sure though.
I think I am on the right path but I'm having trouble cancelling out the mass of the wallet. I drew a free body diagram and know that there are three forces acting on the wallet: gravity, friction, and normal force (including the van's acceleration).
The y-component of the friction and normal...
Hi!
I'm working in a new area and I'm looking for inputs/suggestions for relevant factors to look into and possible ressource where I can read about this :)
I did some tests in a pulley similar to the one below.
I had a fixed weight at M2. I started with M1=M2 but added weights to M1 until...
Homework Statement
A sledge loaded with bricks has a total mass of 18.0 kg and is pulled at constant speed by a rope inclined at 20.0° above the horizontal. The sledge moves a distance of 20.0 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is...
Hello everyone. I find the following problem confusing.
A board sandwiched between two boards in the figure below weighs 95.5N. If friction exists between the middle and the compressing boards, draw the free body diagram of the middle board.
Below I attached the diagram found in the solution...