Two balls are thrown simultaneously, A vertically upwards with a speed of 20 m/s from the ground, and B vertically downwards from a height of 40 m with the same speed along the same line of motion. At what point do the two balls collide? Take `g = 9.8 m//s^(2)`.

Explanation

To solve the problem of the collision between the two balls, we will use the equations of motion. Let's denote the following:

- Ball A is thrown upwards from the ground with an initial velocity \( u_A = 20 \, \text{m/s} \).
- Ball B is thrown downwards from a height of \( h = 40 \, \text{m} \) with an initial velocity \( u_B = 20 \, \text{m/s} \).
- The acceleration due to gravity is \( g = 9.8 \, \text{m/s}^2 \).

### Step 1: Write the equations of motion for both balls.

...