A ball is thrown from ground level so as to just clear a wall 4 m high at a distance of 4 m and fall at a distance of 14 m from the wall. Find the magnitude and direction of the velocity of the ball.

Explanation

To solve the problem of a ball thrown to just clear a wall of height 4 m at a distance of 4 m and then land 14 m away from the wall, we will use the equations of projectile motion. Let's break it down step by step.

### Step 1: Understand the Problem
The ball is thrown from the ground and must clear a wall that is 4 m high, located 4 m away from the launch point. The ball will then travel an additional 14 m, making the total horizontal distance (range) 18 m.

### Step 2: Set Up the Equations
The trajectory of a projectile can be described by the equation:
\[ y = x \tan(\theta) - \frac{g x^2}{2 u^2 \cos^2(\theta)} \]
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