## The Physics of Freefall Speed in Skydiving
When you jump out of an aircraft for a skydive, you’re essentially throwing yourself into a void. And as you plummet towards the earth, you’ll accelerate due to the force of gravity. This acceleration will continue until you reach your terminal velocity, which is the maximum speed you can achieve in freefall.
The terminal velocity of a skydiver is determined by a number of factors, including their weight, body position, and the air density. For an average-sized skydiver in a head-down position, the terminal velocity is about 120 miles per hour.
## How Air Resistance Affects Freefall Speed
As you fall through the air, you’ll experience air resistance, which is a force that opposes your motion. This force is proportional to the square of your velocity, so as you accelerate, the air resistance will increase. Eventually, the air resistance will become equal to the force of gravity, and you’ll reach your terminal velocity.
The amount of air resistance you experience depends on a number of factors, including your body size, shape, and orientation. A skydiver who is spread out like a starfish will experience more air resistance than a skydiver who is in a streamlined head-down position.
## Body Position and Freefall Speed
The position of your body can have a significant impact on your freefall speed. Skydivers typically use three main body positions:
Head-down: This is the most common body position for skydiving. It provides the least amount of air resistance and allows you to reach your terminal velocity quickly.
Head-up: This body position is used for performing flips and other aerial maneuvers. It creates more air resistance than the head-down position, so you’ll decelerate more quickly.
Tracking: This body position is used for flying horizontally. It creates the most air resistance, so you’ll decelerate the most quickly.
## Altitude and Freefall Speed
The altitude from which you jump can also affect your freefall speed. The air is less dense at higher altitudes, so you’ll experience less air resistance and reach your terminal velocity more quickly.
For example, if you jump from 10,000 feet, you’ll reach your terminal velocity of 120 miles per hour in about 10 seconds. However, if you jump from 15,000 feet, you’ll reach your terminal velocity in about 15 seconds.
## Other Factors that Affect Freefall Speed
In addition to the factors discussed above, there are a number of other factors that can affect your freefall speed, including:
Wind speed: A strong wind can help you accelerate or decelerate, depending on the direction of the wind.
Temperature: The temperature of the air can affect its density, which can in turn affect your air resistance.
Equipment: The type of equipment you’re wearing can also affect your air resistance. A skydiving suit, for example, is designed to reduce air resistance.
## Conclusion
The freefall speed of a skydiver is determined by a number of factors, including their weight, body position, the air density, the altitude from which they jump, and the wind speed. By understanding these factors, skydivers can control their freefall speed and perform a variety of aerial maneuvers.