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+ <h2>Solutions of Savchenko Physics Textbook</h2>
+ <p class="author">
+ Aliaksandr Melnichenka <br/>
+ October 2023
+ </p>
+ </header>
+
+ <h3 id="back-link"><a href="../#1.1">$\leftarrow$Back</a></h3>
+
+ <h3> Statement </h3>
+ <p>
+ $1.1.23^*.$ The shooter tries to hit a disk of radius $R$, which moves from one wall to another at constant modulo velocity so fast that it cannot be tracked. Draw a graph of the probability of hitting the disk as a function of the distance between the aiming point and the left wall.
+</p>
+<center>
+ <figure>
+ <img src="statement.png"
+ loading="lazy" width="230" />
+ <figcaption>
+ For problem $1.1.23^*$
+ </figcaption>
+ </figure>
+</center>
+<p>
+The shots are fired at height $R$ from the floor perpendicular to the direction of motion of the disc. At what point is the least and most probable shot? What is their value? Consider the cases $L > 4R$, $4R > L > 2R$, where $L$ is the distance between the walls.
+ </p>
+
+ <h3>Solution</h3>
+ <p>
+
+ <center>
+ <figure>
+ <img src="animation.gif" alt="1.1.23"
+ loading="lazy" width="300" />
+ <figcaption>
+ Wheels moving
+ </figcaption>
+ </figure>
+ </center>
+
+ <p>
+ When the target is moving, a bystander is less likely to see the target from the edge, as it stays there for a shorter period of time.
+ </p>
+ <p>
+ Thus, the maximum probability will be observed on the interval:
+ </p>
+ <p style="text-align: center;">
+ $$\left\{\begin{matrix}
+0 \leq x < 2R\\
+L-2R < x \leq L
+\end{matrix}\right.$$
+ </p>
+ <p>
+ Since the velocity of the target is constant, and finding the target in the range $2R \leq x \leq L-2R$ is equally likely, the probability of finding it in this range is equal to the ratio of the diameter to the length of this range: $\frac{2R}{L-2R}$.
+ </p>
+ <p>
+ Graphs corresponding to these modes:
+ </p>
+
+ <center>
+ <figure>
+ <img id="sol" src="sol.png" alt="1.1.23"
+ loading="lazy" width="350" />
+ <figcaption>
+ Probability of a hit as a function of aiming distance
+ </figcaption>
+ </figure>
+ </center>
+ </p>
+
+ <h4>Answer</h4>
+ <p>
+ <a href="#sol">See Fig.</a> Zero at the walls. The largest at any place at a distance from the walls,
+greater than $2R$, and equal to $2R/(L-2R)$ at $L > 4R$; at any place at a distance from the walls greater than $L - 2R$, and equal to one at $4R > L > 2R$.
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