To find the vertical component of the rock's velocity, we use the initial velocity and the angle of projection. The vertical component of the velocity ($v_{y0}$) can be determined using the following equation:

$v_{y0} = v_0 \sin \theta$

Where:

• $v_0 = 20 \, \text{m/s}$ is the initial velocity of the rock.
• $\theta = 33^\circ$ is the angle of projection.

Now, let's calculate $v_{y0}$:

$v_{y0} = 20 \sin 33^\circ$

Let me calculate this for you.The vertical component of the rock's initial velocity is approximately $10.89 \, \text{m/s}$.

Would you like further details or have any other questions?

Here are five related questions you might consider:

1. What is the horizontal component of the rock's velocity?
2. How long does the rock stay in the air before hitting the ground?
3. What is the height of the building?
4. What is the rock's velocity just before it hits the ground?
5. How far vertically does the rock travel during its motion?

Tip: The vertical and horizontal components of velocity are independent of each other in projectile motion!