The $2$ kg block shown in the figure (top view) rests on a smooth horizontal surface and is attached to a massless elastic cord that has a stiffness $5\: N/m$.
The cord hinged at $\text{O}$ is initially unstretched and always remains elastic. The block is given a velocity $v$ of $1.5\: m/s$ perpendicular to the cord. The magnitude of velocity in $m/s$ of the block at the instant the cord is stretched by $0.4\: m$ is
- $0.83$
- $1.07$
- $1.36$
- $1.50$