A ring of mass m can slide over a smooth vertical rod as shown in figure. The ring is connected to a spring of force constant\[k=4mg\text{ }I\text{ }R\], where 2 R is the natural length of the spring. The other end of spring is fixed to the ground at a horizontal distance 2 R from the base of the rod. If the mass is released at a height 1.5 R, then the velocity of the ring as it reaches the ground is Critical Thinking

• A. \[\sqrt{gR}\]
• B. \[2\sqrt{gR}\]
• C. \[\sqrt{2gR}\]
• D. \[\sqrt{3gR}\]