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Another application is the frictional force spectroscopy in the stick slip mode. There you use an AFM (atomic force microscope) and you move it laterally over the surface (Actually I think you move the sample, but it doesn't matter). You are performing this so slowly that the cantileaver sticks and slips. From these kinds of measurements you can determine ...

2

Yes, grasshoppers use it to create the sounds they use for attracting mates. Actually I don't know of any applications other than generating sounds. As Calmarius mentions in the comment, stringed instruments played with a bow use stick-slip motion to make the string vibrate. In the old days teachers used it to make excruciating noises with chalk on the ...

2

The block is accelerating at $1\frac{m}{s^2}$ up the incline, since it is stationary with respect to the conveyor belt. What force is causing the block to accelerate? It can't be the normal force (which acts perpendicular to the motion). It must be the frictional force, which counteracts the component of gravity parallel to the incline. Using Newton's ...

1

Ultimately, I think the discrepancies you are seeing are due to differences in conditions. As you probably know, the conditions can change the coefficient of friction enormously. Polishing the metal will usually lower the friction, a lubricant will lower the friction, and the temperature will change the viscosity of the lubricant. I'm sure there are others. ...

1

The ground will provide all of the static friction. Imagine what would happen if the upper block contributed even a tiny amount to the static friction: It would have to move forward due to the reaction force. Having M2 inch along you pull M1 (which stays stationary) would be very strange indeed. Static friction always acts to prevent relative motion. It ...

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In the following diagram, is work done by static friction 0 ?, since the point of application is also moving with speed v w.r.t. ground here and is only stationary w.r.t. the block on which sphere is rolling w.r.t. ground here. Static friction itself is 0. The formula $f_s=\mu N$ defines the maximum possible magnitude of the static friction force, not ...

2

How can we apply angular momentum conservation when friction is present? Why not? If we have a closed system, momentum and angular momentum are conserved. In this case, the full system is disk A and disk B, and there are no external forces, so the system is closed. There are internal forces, namely in this case, friction, but that doesn't matter. You ...

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Without friction, the forces during the collision (glancing or head-on) are applied exclusively through their centres of mass. (Illustration available on Wikipedia.) The torque is given by $\tau=\mathbf r \times \mathbf F$ - but if the forces are applied through the centre of mass, then $\mathbf r$ and $\mathbf F$ are parallel, and hence $\tau=0$. Without ...

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A body is said to be executing S.H.M. if it oscillates about a fixed mean position and the motion should be periodic i.e. body takes equal time to reach its mean position in several repetetions......(All S.H.Ms are periodic in nature but all periodic motions are not simple harmonic)......

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Fifteen years ago, there was much research interest in the applicability of fractals to the description of fractures in rocks. In particular, as a mathematical technique for modeling fracture populations, fracture networks, or fracture surfaces in systems exhibiting brittle-failure, fluid flow through porous rock, and sliding friction. I wouldn't say any of ...

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It is common to substitute $\gamma = 2 \zeta \omega_0$. The dimensionless constant $\zeta$ is referred to as the damping ratio. This damping ratio expresses the level of damping relative to critical damping.

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Actually, this is just a simple model for resistive forces (usually duo to viscosity) , and in many situations you can not assume this force to be linearly dependent on velocity.(for example ,usually this model is correct only for small enough objects) In many everyday examples, this force is due to viscous forces. If you consider an (small enough) object ...

3

This question is actually one of the lab exercises I teach. For a spring-mass system, if the damping force is friction, then it is independent of velocity (verified experimentally). However, as mentioned in the comments, the damping force may not always be friction. For example, if the mass is a material like aluminium and it is oscillating over some ...

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This may be a bit of an eye-rolly answer, but since you specifically state that all you care about is minimizing the horizontal force: All you need to do is lower the normal force since the horizontal force you need to apply to get the brick moving needs to overcome the force of friction. Since friction, in the static case, is the coefficient of static ...

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Suppose that you exert the force with angle $\theta$ (with respect to ground). Then you will have: $$\mu(mg-F\sin(\theta))=F\cos(\theta)\text{, so }F=\frac{{\mu}mg}{\cos(\theta)+{\mu}\sin(\theta)}.$$ Now, if you minimize this function with respect to $\theta$ you will find that $$\tan(\theta)=\mu.$$ Replacing this $\theta$ (a function of $\mu$) for ...

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If you can't change the brick or the surface(or the contact eg by lifting the brick) Then how you put the force into the brick doesn't change the energy treansferred

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