# How long will it take for a launched tennis ball to reach the ground?

When a tennis ball is launched horizontally at a speed of 24.4 meters per second and at a height of 2.10 meters above the ground, the key concept to consider is the time for projectile motion, which is determined by the vertical motion of the ball. In this scenario, the ball experiences free fall due to the force of gravity.

To calculate the time it takes for the tennis ball to reach the ground, we can use the equation of motion for vertical motion: y = y₀ + v₀yt - 0.5gt². In this equation, y is the final vertical position, y₀ is the initial vertical position (2.10 meters above the ground), v₀y is the initial vertical velocity (0 m/s for horizontally launched ball), g is the acceleration due to gravity (9.8 m/s²), and t is the time taken.

By substituting the given values into the equation and considering that the final vertical position is 0 meters (ground level), we can solve for the time it takes for the ball to hit the ground. In this case, the time comes out to be approximately 0.65 seconds before the tennis ball makes contact with the ground.

This calculation highlights the importance of understanding the physics principles behind projectile motion and the influence of gravity on objects in motion. By analyzing the initial conditions and applying the appropriate equations, we can determine the time it takes for a tennis ball launched horizontally to reach the ground with precision.