A ball is thrown horizontally from the the top of a building H and lands a distance x from the base of the building. What must have been the initial horizontal component of the velocity v0x?

To determine the initial horizontal component of the velocity (v0x), we can use the equation of motion for horizontal motion:

x = v0x * t

where:
- x is the horizontal distance traveled by the ball
- v0x is the initial horizontal component of the velocity
- t is the time of flight

In this scenario, the ball is thrown horizontally from the top of a building, which means its initial vertical component of the velocity (v0y) is zero. The time of flight (t) can be determined using the vertical kinematics equation:

H = v0y * t + (1/2) * g * t^2

Since v0y = 0, the equation simplifies to:
H = (1/2) * g * t^2

Solving for t, we get:
t = sqrt((2 * H) / g)

Now plug this value of t into the equation for horizontal motion:
x = v0x * t

Solving for v0x, we have:
v0x = x / t

Thus, the initial horizontal component of the velocity (v0x) can be calculated by dividing the horizontal distance traveled (x) by the time of flight (t), where t is determined from the height of the building (H) and the acceleration due to gravity (g).