When an object is thrown upward, the initial velocity (also known as the launch velocity) is the velocity with which it is thrown. The final velocity is the velocity when the object reaches its highest point and starts to fall back down.
In the absence of air resistance, the initial velocity and final velocity have the same magnitude but opposite directions. This is because the object slows down as it moves upward against gravity, eventually comes to a stop at its highest point, and then accelerates downward due to gravity.
At the highest point of its trajectory, the final velocity is zero because the object momentarily comes to rest before falling back down. The initial velocity and final velocity have the same magnitude but opposite signs.
To calculate the final velocity of the object when it reaches its highest point, you can use the following equation:
Final velocity (v_f) = Initial velocity (v_i) - (acceleration due to gravity * time)
Since the object is thrown upward, the initial velocity (v_i) will be positive. The acceleration due to gravity (g) is typically taken as -9.8 m/s² (negative because it acts in the opposite direction of the object's motion), and time (t) will depend on the specific scenario.
Keep in mind that this explanation assumes idealized conditions without air resistance. In real-world scenarios, factors like air resistance may affect the object's motion, altering the exact values of the initial and final velocities.