(Solved): Help! NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return ...

NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. A \( 0.5-\mathrm{kg} \) block \( B \) slides without friction inside a slot cut in arm \( O A \) which rotates in a vertical plane. The rod has a constant angular acceleration \( \vec{\theta}=10 \) radis 2 . Know that when \( \theta=66^{\circ} \) and \( r=0.8 \mathrm{~m} \), the velocity of the block is zero. Determine the relative acceleration of the block with respect to the arm at this instant. The relative acceleration of the block with respect to the arm is \( \mathrm{m}^{2} \mathrm{~s}^{2} \)