A body located on a horizontal plane is pulled by the thread in the horizontal direction. Draw a graph of the dependence of the friction force acting on the body from the plane on the tension force of the thread. Initially, the body is motionless. Body weight 10 kg, coefficient of friction 0.51.

Solutions of Savchenko Problems in Physics

Aliaksandr Melnichenka
October 2023

    <h3 id="back-link"><a href="/#2.1">$\leftarrow$Back</a></h3>

    <h3> Statement </h3>
    <p>
        $2.1.19.$ A body located on a horizontal plane is pulled by the thread in the horizontal direction. Draw a graph of the dependence of the friction force acting on the body from the plane on the tension force of the thread. Initially, the body is motionless. Body weight $10$ kg, coefficient of friction $0.51$.

    <h3>Solution</h3>
    <p>
        <p>

Let's do a visual experiment, put a pen on a piece of paper and slowly move it to the side

At some point, the pen will go in the opposite direction and slip out from under your hand

Using a special program, we will determine the angle of the pen at this moment

It worked $$\boxed{\alpha = 7^{\circ}}$$ Let's display the forces acting on the handle

Since the friction force is the force of static friction $$F_{тр} = \mu N$$ Let us write down the equilibrium condition at the critical moment $$\left\{\begin{matrix} \mu N = F \sin \alpha\\ N = F \cos \alpha \end{matrix}\right.$$ Where $$\boxed{\mu = \tan \alpha}$$ We substitute experimental data $$\mu = \tan 7^{\circ} = 0.12$$

<footer class="row container">
  <br>
    <p>
        <small> © <strong>Savchenko Solutions</strong>, 2023-2024 <br></small>
    </p>
    <p>
        <small>All rights belong to the authors. <br> Commercial use of materials - with the written permission of the authors. <br> alex@savchenkosolutions.com <br></small>
    </p>
</footer>