A body is projected horizontally from the top of a tower with initial velocity `18 m s^-1`. It hits the ground at angle `45^@`. What is the vertical component of velocity when it strikes the ground ?

Explanation

To solve the problem, we need to find the vertical component of the velocity of a body projected horizontally from the top of a tower when it strikes the ground at an angle of 45 degrees.

### Step-by-Step Solution:

1. **Understanding the Problem**:
- A body is projected horizontally with an initial velocity \( u = 18 \, \text{m/s} \).
- It hits the ground at an angle of \( 45^\circ \).

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