# Acceleration of a skydiver free falling(no parachute yet)9.8m/s^2 ?

#### marshall4

is the acceleration of a skydiver free falling(no parachute yet)9.8m/s^2 ?

When the skydiver reaches a new lower terminal velocity, what happens to his weight and drag?

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#### Integral

Staff Emeritus
Gold Member
A skydivers acceleration is a bit less then g, due to drag, until he reaches terminal velocity. At terminal velocity his acceleration is 0.

When the skydiver reaches a new lower terminal velocity, what happens to his weight and drag?
I am not sure what this means.

#### turin

Homework Helper
If you dive head first, like you would into the water, you will reach a much higher terminal velocity than if you spread eagle. So, if you dive head first, reach the terminal velocity, and then go spread eagle, you will swoop through the air at an angle, and the "wind" will slow you to the new slower terminal velocity. Basically, there are two forces, weight and drag. Weight is a consant; drag is much higher spread eagle than head first.

If you go high enough in the atmosphere you can achieve very high speeds:

On August 27, 1960, the record was broken when a U.S. Air Force captain, Joseph Kittinger, Jr., set a world record for the highest balloon ascent, reaching an altitude of 102,800 feet (31,333 meters) in the Excelsior III. At the end of his ascent, he jumped out of his gondola and parachuted to the ground. That descent set another record for the longest parachute freefall—four minutes and 36 seconds—before his main parachute opened at 18,000 feet (5,486 meters). During his descent, he reached speeds of up to 614 miles per hour (1,149 kilometers per hour), approaching the speed of sound without an aircraft or space vehicle. He fell through air temperatures as low as minus 94 degrees Fahrenheit (minus 70 degrees Celsius). His flight and parachute jump demonstrated that it was possible to put a person into space and that fliers could exit their aircraft at extremely high altitudes and freefall back into the Earth's atmosphere.

http://www.centennialofflight.gov/essay/Lighter_than_air/20th_cent_records-2/LTA12.htm [Broken]

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#### russ_watters

Mentor
Re: Skydiving

Originally posted by marshall4
When the skydiver reaches a new lower terminal velocity, what happens to his weight and drag?
At terminal velocity, weight = drag.

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