Understanding the Physics

* Free Fall: When a ball is thrown upwards, it's under the influence of gravity, which causes it to decelerate. This means its upward velocity decreases as it rises.

* Symmetry: The motion of the ball going up and coming back down is symmetrical. This means the speed at which it's going upwards at a certain height is the same as the speed it's going downwards at that same height.

* Velocity at the Highest Point: At the highest point, the ball's instantaneous velocity is zero.

Solving the Problem

1. Velocity at 2 seconds before the highest point: Since the motion is symmetrical, the velocity 2 seconds before the highest point is the same magnitude as the velocity 2 seconds after the highest point (when it's falling back down).

2. Applying the Equation: We can use the following equation to find the velocity:

* v = u + at

Where:

* v = final velocity (what we want to find)

* u = initial velocity (0 m/s at the highest point)

* a = acceleration due to gravity (approximately -9.8 m/s²)

* t = time (2 seconds)

3. Calculation:

* v = 0 + (-9.8 m/s²) * 2 s

* v = -19.6 m/s

Answer: The velocity of the ball 2 seconds before it reaches the highest point is -19.6 m/s. The negative sign indicates that the velocity is directed downwards.