The system is released from rest at $=0$ when a constant couple moment $M=100N*m$ is applied.

$($Figure $1)$

Figure

Part A

If the mass of the cable and links $AB$ and $BC$ can be neglected, and each pulley can be treated as

a disk having a mass of $6$ kg $,$ determine the speed of the $18-kg$ block at the instant link $AB$ has

rotated $=90.$ Note that point $C$ moves along the vertical guide. Also, the cable does not slip on

the pulleys.

Express your answer to three significant figures and include the appropriate units.