A bullet of mass 10 g and speed $500 \mathrm {~m} / \mathrm { s }$ is fired into a door and gets embedded exactly at the centre of the door. The door is 1.0 m wide and weighs 12 kg . It is hinged at one end and rotates about a vertical axis practically without friction. The angular speed of the door just after the bullet embeds into it will be : (1) $6.25 \mathrm { rad } / \mathrm { sec }$ (2) $0.625 \mathrm { rad } / \mathrm { sec }$ (3) $3.35 \mathrm { rad } / \mathrm { sec }$ (4) $0.335 \mathrm { rad } / \mathrm { sec }$
A bullet of mass 10 g and speed $500 \mathrm {~m} / \mathrm { s }$ is fired into a door and gets embedded exactly at the centre of the door. The door is 1.0 m wide and weighs 12 kg . It is hinged at one end and rotates about a vertical axis practically without friction. The angular speed of the door just after the bullet embeds into it will be :\\
(1) $6.25 \mathrm { rad } / \mathrm { sec }$\\
(2) $0.625 \mathrm { rad } / \mathrm { sec }$\\
(3) $3.35 \mathrm { rad } / \mathrm { sec }$\\
(4) $0.335 \mathrm { rad } / \mathrm { sec }$