\( \mathrm{A} \operatorname{rod} \mathrm{AB} \) is shown in figure. End \( \mathrm{A} \) of the ....

\( \mathrm{A} \operatorname{rod} \mathrm{AB} \) is shown in figure. End \( \mathrm{A} \) of the rod is fixed on the ground. Block is moving with velocity
\( \mathrm{P} \)
\( \sqrt{3} \mathrm{~m} / \mathrm{s} \) towards right. The velocity of end \( \mathrm{B} \) of \( \mathrm{rod} \) when rod makes an angle of \( 60^{\circ} \) with the ground is
(1) \( \sqrt{3} \mathrm{~m} / \mathrm{s} \)
(2) \( 2 \mathrm{~m} / \mathrm{s} \)
(3) \( 2 \sqrt{3} \mathrm{~m} / \mathrm{s} \)
(4) \( 3 \mathrm{~m} / \mathrm{s} \)