An object dropped and an object thrown horizontally from the same height will hit the ground at the same time.

Here's why:

* Gravity acts equally on both objects: Both objects experience the same acceleration due to gravity, which is the only force acting on them vertically.

* Horizontal motion doesn't affect vertical motion: The horizontal velocity of the thrown object doesn't influence how quickly it falls.

Think of it this way:

Imagine two balls, one dropped straight down and the other thrown horizontally. The ball thrown horizontally will move forward as it falls, but it will fall at the same rate as the ball dropped straight down. They will both reach the ground simultaneously.

This principle is why you can't simply throw a ball horizontally to make it stay in the air longer. It will fall at the same rate regardless.