# Acceleration Due to Gravity

## Understand and state acceleration due to gravity and the value of g

Estimated13 minsto complete
%
Progress
Practice Acceleration Due to Gravity

MEMORY METER
This indicates how strong in your memory this concept is
Progress
Estimated13 minsto complete
%
The Art of Falling

### The Art of Falling

Credit: U.S. Army
Source: http://www.flickr.com/photos/soldiersmediacenter/2990718614/
License: CC BY-NC 3.0

After jumping out of a plane that is flying 10,000 feet above the Earth's surface, this skydiver reached speeds of up to 120 miles per hour before deploying his parachute. Within a matter of seconds the increased surface area reduced his velocity to safe enough levels for landing. By using Newton?s 2nd law, you can easily calculate his landing speed.

#### New You Can Use

Credit: wales_gibbons
Source: http://www.flickr.com/photos/9678460@N07/7462872938
License: CC BY-NC 3.0

Skydivers free fall before deploying their parachutes [Figure2]

• Since the early 1100s, people have been using parachutes to skydive. Even though they didn?t know it, they were using the most basic principles of physics. By using a parachute, the effective surface area of the falling body is increased allowing for more air to be ?caught?.
• Effective parachutes will expose a skydiver to 3-4 g's of negative acceleration when the parachute is deployed. This causes the skydiver?s velocity to go from 120 miles per hour to roughly only 18 miles per hour in a matter of seconds. With the forces balanced, the skydiver will be able to safely land.

#### Show What You Know

Using the information provided above, answer the following questions.

1. When the skydiver is falling at a constant velocity after the parachute is open, what is their acceleration?
2. Explain why it is not advised to use a parachute that is as big as possible, assuming you could safely deploy it?
3. At what point in the skydiving experience is the acceleration due to gravity equal to zero?

### Notes/Highlights Having trouble? Report an issue.

Color Highlighted Text Notes
Please to create your own Highlights / Notes

1. [1]^ Credit: U.S. Army; Source: http://www.flickr.com/photos/soldiersmediacenter/2990718614/; License: CC BY-NC 3.0
2. [2]^ Credit: wales_gibbons; Source: http://www.flickr.com/photos/9678460@N07/7462872938; License: CC BY-NC 3.0

### Explore More

Sign in to explore more, including practice questions and solutions for Acceleration Due to Gravity.