## A 67.2 kg Falling Skydiver Opens His Parachute: Physics in Action

### Introduction

Skydiving is an exhilarating sport that involves jumping out of an airplane and freefalling until deploying a parachute to slow the descent. The physics behind skydiving is fascinating, as it involves a combination of gravity, air resistance, and aerodynamics.

### Freefall Phase

When the skydiver jumps out of the plane, he experiences a brief period of freefall, during which the only force acting on him is gravity. This causes him to accelerate downwards at a rate of 9.8 m/s². The skydiver’s velocity increases as he falls, and the air resistance he encounters also increases.

### Parachute Deployment

As the skydiver reaches a certain velocity, he deploys his parachute. The parachute is designed to create a large surface area, which increases the air resistance acting on the skydiver. This causes a sudden decrease in his velocity and acceleration.

### Parachute Deployment Physics

The physics of parachute deployment can be described using the following equation:

“`

F = ma

“`

Where:

F is the net force acting on the skydiver

m is the mass of the skydiver

a is the acceleration of the skydiver

When the skydiver deploys his parachute, the net force acting on him changes. The force of gravity remains the same, but the force of air resistance increases significantly. This causes the skydiver’s acceleration to decrease.

### Calculating Terminal Velocity

The terminal velocity of a skydiver with a parachute is the constant velocity that the skydiver reaches after the parachute has fully deployed. The terminal velocity can be calculated using the following equation:

“`

v = √(2mg/ρCA)

“`

Where:

v is the terminal velocity

m is the mass of the skydiver

g is the acceleration due to gravity

ρ is the density of air

C is the drag coefficient of the parachute

A is the area of the parachute

### Practical Implications

The physics of parachute deployment has a number of practical implications for skydiving. First, it helps to ensure that the skydiver does not reach a dangerous velocity during freefall. Second, it allows the skydiver to control his descent rate and land safely.

### Conclusion

The physics behind skydiving is fascinating and complex. By understanding the principles of gravity, air resistance, and aerodynamics, skydivers can enjoy a safe and exhilarating experience.