The force exerted is:
\[ F = \frac{\Delta P}{\Delta t}. \]
Here:
\[ \Delta P = m \cdot v - 0 = 150 \times 10^{-3} \cdot 20 \, \text{kg m/s}, \]
\[ F = \frac{150 \times 10^{-3} \cdot 20}{0.1}. \]
\[ F = 30 \, \text{N}. \]
Final Answer: 30 N.
Let $ P_n = \alpha^n + \beta^n $, $ n \in \mathbb{N} $. If $ P_{10} = 123,\ P_9 = 76,\ P_8 = 47 $ and $ P_1 = 1 $, then the quadratic equation having roots $ \alpha $ and $ \frac{1}{\beta} $ is: