The two springs are connected in parallel, meaning that they experience the same displacement when the mass oscillates.
For springs in parallel, the equivalent spring constant (\( K_{eq} \)) is the sum of the individual spring constants:
\( K_{eq} = K_1 + K_2 \)
The time period (T) of oscillation for a mass-spring system is given by:
\( T = 2\pi \sqrt{\frac{m}{K}} \)
where \( m \) is the mass and \( K \) is the spring constant. In this case, we use the equivalent spring constant:
\( T = 2\pi \sqrt{\frac{m}{K_{eq}}} = 2\pi \sqrt{\frac{m}{K_1 + K_2}} \)
The time period of oscillation of mass \( m \) is \( \mathbf{2\pi \sqrt{\frac{m}{K_1+K_2}}} \) (Option 4).
The center of a disk of radius $ r $ and mass $ m $ is attached to a spring of spring constant $ k $, inside a ring of radius $ R>r $ as shown in the figure. The other end of the spring is attached on the periphery of the ring. Both the ring and the disk are in the same vertical plane. The disk can only roll along the inside periphery of the ring, without slipping. The spring can only be stretched or compressed along the periphery of the ring, following Hooke’s law. In equilibrium, the disk is at the bottom of the ring. Assuming small displacement of the disc, the time period of oscillation of center of mass of the disk is written as $ T = \frac{2\pi}{\omega} $. The correct expression for $ \omega $ is ( $ g $ is the acceleration due to gravity):
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: