In the above problem, what is the component of its velocity perpendicular to the plane when it strikes at A ?

Explanation

To solve the problem of finding the component of the velocity perpendicular to the plane when the projectile strikes at point A, we can follow these steps:

### Step-by-Step Solution

1. **Identify the Initial Conditions**:
- The projectile is launched at an angle of 30 degrees with an initial velocity \( U = 10 \, \text{m/s} \).
- The vertical component of the initial velocity \( U_y \) can be calculated using the sine function:
\[
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