1. A disk rotates around a vertical axis with frequency p. The axis passes through the center of the disk. The surface of the disk is horizontal and smooth. A small washer is tied to the axis with a light thread, lies on the disk, and rotates with it. The radius of the disk is $R$, the length of the thread is $R / 4$. The thread breaks. After what time will the washer leave the disk?
```
\begin{aligned}
& V_{0}=2 \pi n \cdot \frac{R}{4} \\
& l=\sqrt{R^{2}-(R / 4)^{2}}=\frac{\sqrt{15}}{4} R \\
& T=\frac{l}{V_{0}}=\frac{\sqrt{15} R}{4} \cdot \frac{4}{2 \pi n R}=\frac{\sqrt{15}}{2 \pi n}
\end{aligned}
```