163- A light spring with constant $200\,\dfrac{\text{N}}{\text{m}}$ is attached to the ceiling of an elevator, and a mass $m = 5\,\text{kg}$ is hung from it. The elevator descends with acceleration $2\,\dfrac{\text{m}}{\text{s}^2}$ and the length of the spring is $L_1$. When the elevator descends with acceleration $1\,\dfrac{\text{m}}{\text{s}^2}$, the spring becomes $L_2$. What is the difference $L_2 - L_1$ in centimeters? $\left(g = 10\,\dfrac{\text{m}}{\text{s}^2}\right)$ $$15 \ (1) \qquad\qquad 7.5 \ (2) \qquad\qquad 5 \ (3) \qquad\qquad 2.5 \ (4)$$
\textbf{163-} A light spring with constant $200\,\dfrac{\text{N}}{\text{m}}$ is attached to the ceiling of an elevator, and a mass $m = 5\,\text{kg}$ is hung from it. The elevator descends with acceleration $2\,\dfrac{\text{m}}{\text{s}^2}$ and the length of the spring is $L_1$. When the elevator descends with acceleration $1\,\dfrac{\text{m}}{\text{s}^2}$, the spring becomes $L_2$. What is the difference $L_2 - L_1$ in centimeters? $\left(g = 10\,\dfrac{\text{m}}{\text{s}^2}\right)$
$$15 \ (1) \qquad\qquad 7.5 \ (2) \qquad\qquad 5 \ (3) \qquad\qquad 2.5 \ (4)$$
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